History of Services 171 - 180

Service 171

Operator	Route	Year	Date	Service changes
UBC	Sembawang Ter ↔ Queen St (1971 - 1987)	1971	11 April	Introduced between Sembawang Ter and Queen St Ter under 1971 Bus Reorganisation.
		1973	25 June	Amended to ply Mandai Lake Rd in both directions until 2200 hours daily.
		1979	28 October	Amended to ply Sungei Rd, Ophir Rd and Ban San St (towards Queen St Ter) and amended to ply Rochor Canal Rd and Bt Timah Rd, skipping Bencoolen St, Middle Rd, Selegie Rd and Mackenzie Rd (towards Sembawang Ter) with the conversion of Rochor Canal Rd and Rochor Rd to one-way traffic.
			30 December	Amended to ply Jln Anak Bt towards Queen St Ter with the partial conversion of Upp Bt Timah Rd to one-way traffic.
		1984	15 April	Amended to ply Scotts Rd, Orchard Rd and Victoria St/Nth Bridge Rd, skipping Bt Timah Rd and Sungei Rd/Rochor Canal Rd.
		1985	13 October	Amended to the relocated Queen St Ter along Ban San St, skipping Arab St.
	Yishun ↔ Queen St (1987 - 1993)	1987	18 January	Amended to Yishun Ctrl Ter.
			23 August	Amended to Yishun Int.
			13 December	Serves new staggered bus stop outside Orchard Stn along Orchard Blvd, skipping the bus stop opposite Orchard Stn.
				Serves new bus stop outside Newton Stn along Scotts Rd.
		1992	19 July	Amended to ply Orchard Lk due to the closure of Grange Rd to facilitate road expansion works.
	Yishun ↔ Marina Ctr (1993 - 2020)	1993	3 January	Extended to Marina Ctr Ter and amended to ply Bt Panjang Rd, Pending Rd and Cashew Rd under TransitLink Network Integration Exercise Phase 11.
		1994	26 April	Amended to skip Mandai Lake Rd and amended to ply Mandai Ave with the introduction of Service 138.
		1995	7 May	Amended to ply Orchard Turn.
			5 November	Operations transferred to TIBS.
				First bus from Yishun Int revised to 0530 hrs daily.
		1999	26 December	Amended to ply BKE, Bt Panjang Rd, Petir Rd, Jelebu Rd under Bt Panjang LRT Rationalisation, skipping Woodlands Rd and Cashew Rd.
		2000	TBC	Serves new bus stop before Goldhill Ave along Dunearn Rd.
			TBC	Serves additional bus stop opposite Sembawang Air Base along Sembawang Rd.
		2002	TBC	Serves the bus stop outside Blk 923 along Yishun Ave 2, skipping the bus stop outside Northpoint Shop Ctr.
			7 July	Skips the bus stop outside Orchard Emerald along Orchard Rd.
		2003	TBC	Serves the bus stop outside Northpoint Shop Ctr along Yishun Ave 2, skipping the bus stop outside Blk 923.
Template:SMRT Buses		2005	2 July	Amended to ply Grange Rd and Orchard Lk with the partial closure of Somerset Rd.
		2006	29 October	Serves relocated bus stop outside Orchard Stn along Orchard Turn.
		2009	1 June	Designated wheelchair-accessible bus service (WAB).
			21 June	Serves new pair of bus stops outside and opposite Mandai Crematorium & Columbarium along Mandai Ave.
		2010	23 May	Skips temporarily closed bus stop outside Assumption Voc Inst along Upp Bt Timah Rd to facilitate the construction of Cashew MRT station along the Downtown MRT Line.
		2011	4 September	Serves new bus stop outside Botanic Gdns Stn along Bt Timah Rd.
		2015	1 March	Serves reinstated bus stop outside Assumption Pathway Sch along Upp Bt Timah Rd.
			14 March	Amended to Yishun Temp Int.
			27 December	Serves new bus stop outside Blk 184 along Bt Panjang Rd, skipping the bus stop outside Blk 183.
		2017	4 September	Skips a pair of bus stops outside and opposite Bt Panjang Plaza along Jelebu Rd.
		2018	25 February	Serves additional pair of bus stops outside and opposite Blk 180 along Jelebu Rd.
		2019	8 September	Amended to Yishun Integrated Transport Hub.
	Yishun ↺ Bt Panjang Stn (since 2020)	2020	30 August	Shortened to loop at Upp Bt Timah Rd from Yishun Int under Downtown MRT Line 2 Rationalisation.
(Current)		2021	5 September	Operations transferred to Tower Transit Singapore.

Service 172

Operator	Route	Year	Date	Service changes
UBC	Lim Chu Kang ↔ Prince Edward (1971 - 1987)	1971	11 April	Introduced between Lim Chu Kang Ter and Prince Edward Ter under 1971 Bus Reorganisation.
		1974	3 February	Amended to skip Choa Chu Kang Rd End under 1974 Bus Rationalisation.
			8 December	Amended to ply Cecil St, skipping Robinson Rd.
		1976	14 March	Serves new staggered bus stop outside The Cenotaph along Connaught Dr, skipping the bus stop opposite Singapore Cricket Club.
		1979	11 February	Amended to ply the extended Shenton Way, Palmer Rd and Anson Rd, skipping Parsi Rd.
			28 October	Amended to ply Sungei Rd towards Prince Edward Ter with the conversion of Rochor Canal Rd to one-way traffic.
			30 December	Amended to ply Jln Anak Bt towards Prince Edward Ter with the partial conversion of Upp Bt Timah Rd to one-way traffic.
		1980	TBC	Amended to ply Bt Timah Rd towards Lim Chu Kang Ter, skipping Mackenzie Rd.
	Lim Chu Kang ↔ Shenton Way (1987 - 1991)	1987	28 June	Amended to Shenton Way Ter.
	Lim Chu Kang ↺ Jln Anak Bt (1991 - 1993)	1991	26 May	Shortened to loop at Jln Anak Bt from Lim Chu Kang Ter under TransitLink Network Integration Exercise Phase 5.
	Boon Lay ↺ Jln Anak Bt (1993 - 1999)	1993	3 January	Amended to Boon Lay Int under TransitLink Network Integration Exercise Phase 11.
		1994	TBC	Amended to ply Sg Tengah Rd with the partial closure of Choa Chu Kang Rd.
		1998	TBC	Serves new pair of bus stops outside and opposite Blk 464 along Choa Chu Kang Ave 3.
	Boon Lay ↔ Choa Chu Kang (1999 - 2006)	1999	26 December	Operations transferred to TIBS.
				Shortened to Choa Chu Kang Int under Bt Panjang LRT Rationalisation.
		2001	TBC	Serves new bus stop outside Sunshine Pl along Choa Chu Kang Ave 3.
Template:SMRT Buses (Current)	Boon Lay Temp Int ↔ Choa Chu Kang (2006 - 2009)	2006	18 June	Amended to Boon Lay Temp Int.
		2009	1 June	Designated wheelchair-accessible bus service (WAB).
	Boon Lay ↔ Choa Chu Kang (since 2009)		27 December	Amended to Boon Lay Integrated Transport Hub.
		2011	23 October	Skips a pair of removed bus stops after LP 222 and B27 Old Choa Chu Kang Rd along Old Choa Chu Kang Rd.
		2013	24 February	Serves new bus stop outside Blk 293 along Choa Chu Kang Ave 1.
		2018	16 December	Amended to new Choa Chu Kang Int.

Service 173

Operator	Route	Year	Date	Service changes
UBC	Princess Elizabeth ↔ New Bridge Rd (1971 - 1990)	1971	11 April	Introduced between Princess Elizabeth Ter and New Bridge Rd Ter under 1971 Bus Reorganisation.
		1974	24 February	Amended to ply Grange Rd, Orchard Blvd and Paterson Rd towards Princess Elizabeth Ter with the conversion of Orchard Rd to one-way traffic.
		1979	30 December	Amended to ply Jln Anak Bt towards New Bridge Rd Ter with the partial conversion of Upp Bt Timah Rd to one-way traffic.
		1986	16 November	Serves new staggered bus stop outside Thong Teck Bldg along Scotts Rd, skipping the bus stop outside Metro Orchard.
		1987	6 June	Amended to the relocated New Bridge Rd Ter.
			27 September	Amended to ply the extended Eu Tong Sen St towards Princess Elizabeth Ter to facilitate the first stage of road expansion along New Bridge Rd.
			1 November	Amended to ply Eu Tong Sen St towards Princess Elizabeth Ter to facilitate the second stage of road expansion along New Bridge Rd.
			13 December	Serves new staggered bus stop outside Orchard Stn along Orchard Blvd, skipping the bus stop opposite Orchard Stn.
		1989	29 January	Serves relocated bus stop opposite Sri Mariamman Tp along South Bridge Rd, skipping a removed bus stop opposite Jamae Mque.
	Bukit Batok ↺ Jln Anak Bt (1990 - 1991)	1990	11 March	Extended to start from Bt Batok Int and shortened to loop at Jln Anak Bt.
	Bukit Batok ↔ Clementi (1991 - 1993)	1991	7 April	Integrated with Service 205 and extended to Clementi Int under TransitLink Network Integration Exercise Phase 3.
		1992	3 May	Amended to ply the western loop of Bt Batok Ctrl and Bt Batok St 21 under TransitLink Network Integration Exercise Phase 7, skipping Bt Batok East Ave 3.
	Bukit Batok ↺ Clementi (since 1993)	1993	5 December	Converted to loop service between Bt Batok Int and Clementi Int with the introduction of Service 156 under TransitLink Network Integration Exercise Phase 13.
		2000	24 December	Operations transferred to TIBS.
		2003	12 October	Serves bus stop opposite Bt Timah Plaza along Jln Anak Bt with the removal of the bus stop under the PIE Flyover.
Template:SMRT Buses		2006	16 July	Amended to ply Bt Batok Ave 1 and Bt Batok East Ave 6 and amended to ply Hume Ave, skipping Hillview Rd.
			29 October	Amended to loop at Clementi Temp Int.
		2011	26 November	Amended to loop at Clementi Integrated Transport Hub.
		2013	21 April	Designated wheelchair-accessible bus service (WAB).
		2015	27 December	Amended to ply the upgraded Upp Bt Timah Rd towards Clementi Int, skipping Jln Anak Bt.
(Current)		2016	29 May	Operations transferred to Tower Transit Singapore.

Short Trip 173A (1999 - 2007)

Operator	Year	Date	Service changes
	1999	TBC	Introduced from Jln Anak Bt (PIE Flyover) to Jln Jurong Kechil (Bef Upp Bt Timah Rd) during morning peak hours on weekdays.
	2000	24 December	Operations transferred to TIBS.
	2003	12 October	Starts from the bus stop opposite Bt Timah Plaza along Jln Anak Bt with the removal of the bus stop under the PIE Flyover.
Template:SMRT Buses	2006	29 October	Amended to Clementi Temp Int.
	2007	TBC	Discontinued.

Short Trip 173A (since 2007)

Operator	Year	Date	Service changes
Template:SMRT Buses	2007	11 November	Introduced from Bt Batok Int to Bt Batok East Ave 4 (Blk 254), operating after the last bus of Service 173 daily.
	2013	TBC	Last bus extended to 0100 hrs daily.
		21 April	Designated wheelchair-accessible bus service (WAB).
(Current)	2016	29 May	Operations transferred to Tower Transit Singapore.
	2019	5 October	Last bus extended to 0110 hrs daily.

Service 174

Operator	Route	Year	Date	Service changes
UBC	Nanyang Technological Institute ↔ New Bridge Rd (1971 - 1991)	1971	11 April	Introduced between Nanyang University Ter and New Bridge Rd Ter under 1971 Bus Reorganisation.
		1974	24 February	Amended to ply Grange Rd, Orchard Blvd and Paterson Rd towards Nanyang University Ter with the conversion of Orchard Rd to one-way traffic.
		1975	9 November	Amended to ply Farrer Rd, Holland Rd and Napier Rd, skipping Stevens Rd and Scotts Rd.
				Amended to realigned Jurong Rd, skipping Old Jurong Rd.
		1977	19 June	Amended to ply Orchard Blvd and Grange Rd towards Nanyang University Ter with the full conversion of Orchard Rd to one-way traffic.
		1979	30 December	Amended to ply Jln Anak Bt towards New Bridge Rd Ter with the partial conversion of Upp Bt Timah Rd to one-way traffic.
		1982	23 August	Amended to serve NTI via Nanyang Cres and Nanyang Circle between 0600 hrs and 1800 hrs on weekdays & Saturdays.
		1984	20 October	Amended to ply Bt Batok East Ave 3, Bt Batok St 24, Bt Batok St 23 and interim road with the partial closure of Jurong Rd (between Bt Batok East Ave 3 and Bt Batok St 23).
		1985	17 March	Amended to ply Bt Batok Rd, Bt Batok West Ave 3, Bt Batok Ctrl and Bt Batok East Ave 3 with the partial closure of Jurong Rd.
			30 November	Amended to ply along the new carriageway of Upp Jurong Rd (between Jln Boon Lay and Benoi Rd).
		1986	23 March	Amended to ply Jln Bahar, skipping Upp Jurong Rd.
		1987	22 February	Amended to relocated NTI Ter.
				Amended to ply Nanyang Ave, Nanyang Cres and Nanyang Dr.
			6 June	Amended to the relocated New Bridge Rd Ter.
			27 September	Amended to ply the extended Eu Tong Sen St towards Nanyang Technological Institute Ter to facilitate the first stage of road expansion along New Bridge Rd.
			1 November	Amended to ply Eu Tong Sen St towards Nanyang Technological Institute Ter to facilitate the second stage of road expansion along New Bridge Rd.
		1988	20 March	Amended to ply Upp Cross St and New Bridge Rd, skipping Neil Rd.
		1990	3 June	Amended to ply Nanyang Circle and Student Wk, skipping Nanyang Ave.
		1991	20 January	Amended to ply Nanyang Dr, skipping Nanyang Cres.
	Boon Lay ↔ New Bridge Rd (1991 - 2006)		7 April	Shortened to Boon Lay Int under TransitLink Network Integration Exercise Phase 3.
		1992	19 July	Amended to ply Orchard Lk due to the closure of Grange Rd to facilitate road expansion works.
		1993	TBC	Amended to ply PIE with the partial closure of Jurong Rd.
		1996	TBC	Serves new bus stop outside Blk 220 along Boon Lay Ave.
		1997	7 December	Amended to ply South Bridge Rd and Kreta Ayer Rd with the partial closure of New Bridge Rd to facilitate the construction of Chinatown MRT station on the North East MRT Line.
		2000	20 February	Serves additional bus stop opposite Blk 333 along Kreta Ayer Rd.
Template:SBS Transit (Current)		2002	20 April	Amended to ply Upp Cross St and the reinstated New Bridge Rd, skipping Sth Bridge Rd and Kreta Ayer Rd.
			7 July	Skips the bus stop outside Orchard Emerald along Orchard Rd.
		2003	TBC	Serves new bus stop outside Goh & Goh Bldg along Jln Jurong Kechil.
			7 December	Amended to ply Upp Cross St/Havelock Rd, Chin Swee Rd and Outram Rd.
		2004	TBC	Skips removed bus stop outside Nanyang Pr Sch along Farrer Rd.
		2005	2 July	Amended to ply Grange Rd with the partial closure of Somerset Rd.
	Boon Lay Temp Int ↔ New Bridge Rd (2006 - 2009)	2006	18 June	Amended to Boon Lay Temp Int.
		2008	14 July	Designated wheelchair-accessible bus service (WAB).
	Boon Lay ↔ New Bridge Rd (2009 - 2018)	2009	27 December	Amended to Boon Lay Integrated Transport Hub.
		2011	14 August	Serves additional bus stop outside Clarke Quay Stn along Eu Tong Sen St.
		2012	9 December	Amended to ply Upp Bt Timah Rd and Bt Timah Lk with the partial closure of Jln Jurong Kechil to facilitate the construction of Beauty World MRT station on the Downtown MRT Line.
		2014	26 January	Amended to ply the reinstated Jln Jurong Kechil, skipping Upp Bt Timah Rd and Bt Timah Lk.
		2017	23 April	Serves new bus stop after Bt Batok West Ave 3 along Bt Batok Rd with the relocation of the bus stop before PIE.
	Boon Lay ↔ Kampong Bahru (since 2018)	2018	10 March	Extended to Kg Bahru Ter with the closure of New Bridge Rd Ter.
				First bus from Kg Bahru Ter brought forward to 0540 hrs daily.
		2020	27 September	Amended to ply PIE with the permanent closure of Jurong Rd.

Service 175 (1971 - 1991)

Operator	Route	Year	Date	Service changes
UBC	Upp Jurong Rd ↔ Prince Edward (1971 - 1983)	1971	11 April	Introduced between Upp Jurong Rd Ter and Prince Edward Ter under 1971 Bus Reorganisation.
		1974	8 December	Amended to ply Cecil St, skipping Robinson Rd.
		1975	9 November	Amended to realigned Jurong Rd, skipping Old Jurong Rd.
		1979	11 February	Amended to ply the extended Shenton Way, Palmer Rd and Anson Rd, skipping Parsi Rd.
			28 October	Amended to ply Sungei Rd towards Prince Edward Ter with the conversion of Rochor Canal Rd to one-way traffic.
			30 December	Amended to ply Jln Anak Bt towards Prince Edward Ter with the partial conversion of Upp Bt Timah Rd to one-way traffic.
		1980	2 January	Amended to the relocated Upp Jurong Rd Ter along Jln Ahmad Ibrahim.
			TBC	Amended to ply Bt Timah Rd towards Upp Jurong Rd Ter, skipping Mackenzie Rd.
	Pioneer Rd ↔ Prince Edward (1983 - 1987)	1983	30 October	Amended to Pioneer Rd Ter.
		1984	20 October	Amended to ply Bt Batok East Ave 3, Bt Batok St 24, Bt Batok St 23 and interim road with the partial closure of Jurong Rd (between Bt Batok East Ave 3 and Bt Batok St 23).
		1985	17 March	Amended to ply Bt Batok Rd, Bt Batok West Ave 3, Bt Batok Ctrl and Bt Batok East Ave 3 with the partial closure of Jurong Rd.
			30 November	Amended to ply along the new carriageway of Upp Jurong Rd (between Jln Boon Lay and Benoi Rd).
		1986	4 May	Amended to skip Jurong Cres.
	Pioneer Rd ↔ Shenton Way (1987 - 1989)	1987	28 June	Amended to Shenton Way Ter.
		1989	23 July	Serves new pair of bus stops near Pioneer Rd along Tuas Rd.
	Bukit Batok ↺ Tuas Rd (1989 - 1990)		6 November	Shortened to start from Bt Batok Int and loop at Tuas Rd.
	Bukit Batok ↺ Jurong West St 91 (1990 - 1991)	1990	7 July	Shortened to loop at Jurong West St 91, skipping Tuas Rd.
		1991	20 January	Discontinued under TransitLink Network Integration Exercise Phase 2.

Service 175 (1993 - 2005)

Operator	Year	Date	Service changes
	1993	18 July	Introduced between Lim Chu Kang Ter and Upp Bt Timah Rd (Loop).
	1994	TBC	Amended to ply Sg Tengah Rd with the partial closure of Choa Chu Kang Rd.
	1997	TBC	Serves new bus stop outside Lot 1 Shoppers' Mall along Choa Chu Kang Ave 4.
	1998	TBC	Serves new pair of bus stops outside and opposite Blk 464 along Choa Chu Kang Ave 3.
	1999	26 December	Operations transferred to TIBS.
	2001	TBC	Serves new bus stop outside Sunshine Pl along Choa Chu Kang Ave 3.
Template:SMRT Buses	2005	27 February	Amended to start from Bt Panjang Int, loop at Lim Chu Kang Rd and re-numbered Service 975, skipping Choa Chu Kang Int and Upp Bt Timah Rd.

Service 175 (since 2007)

Operator	Route	Year	Date	Service changes
Template:SBS Transit (Current)	Clementi ↔ Lor 1 Geylang (since 2007)	2007	11 March	Introduced between Clementi Temp Int and Lor 1 Geylang Ter, operating between 0600 hrs and 2330 hrs from Clementi Temp Int and Lor 1 Geylang Ter daily.
			24 June	Serves new bus stop outside Blk 114 along Depot Rd.
		2011	26 November	Amended to Clementi Integrated Transport Hub.
			3 December	Designated wheelchair-accessible bus service (WAB).
		2013	10 March	Serves new bus stop after West Coast Highway along West Coast Lk.

Service 175A (1980 - 1983)

Operator	Year	Date	Service changes
	1980	2 January	Introduced between Upp Jurong Rd Ter and Tuas Village (Loop).
	1983	30 October	Discontinued.

Service 176 (1971 - 1983)

Operator	Route	Year	Date	Service changes
UBC	Corporation Dr ↔ Prince Edward (1971 - 1974)	1971	11 April	Introduced between Corporation Dr Ter and Prince Edward Ter under 1971 Bus Reorganisation.
	Corporation Dr ↔ Crawford St (1974 - 1977)	1974	3 February	Extended to Crawford St Ter under 1974 Bus Rationalisation.
			8 December	Amended to ply the extended Robinson Rd, skipping Market St.
		1976	15 February	Serves new staggered bus stop between Bank of India and Hong Leong Holdings along Robinson Rd.
			14 March	Serves new staggered bus stop outside The Cenotaph along Connaught Dr, skipping the bus stop opposite Singapore Cricket Club.
	Boon Lay Gardens ↔ Crawford St (1977 - 1978)	1977	28 March	Extended to Boon Lay Gdns Ter.
		1978	15 January	Amended to ply Jln Sultan and Beach Rd.
	Clementi ↔ Crawford St (1978 - 1979)		1 June	Shortened to Clementi Ter with the opening of Jurong Int.
		1979	11 February	Amended to ply the extended Shenton Way towards Clementi Ter, skipping Parsi Rd and Anson Rd.
	Clementi ↺ Empress Pl (1979 - 1983)		25 November	Shortened to loop at Empress Pl from Clementi Ter.
		1980	16 November	Amended to Clementi Int.
		1981	21 June	Amended to skip Nepal Circus towards Empress Pl.
			11 October	Serves new staggered bus stop outside Tunas Bldg along Anson Rd, skipping the bus stop outside Intl Plaza.
		1983	26 December	Integrated with Service 146 and discontinued.

Service 176 (since 1988)

Operator	Route	Year	Date	Service changes
	Jurong East ↺ Bukit Panjang (1988 - 1990)	1988	24 January	Introduced between Jurong East Int and Bt Panjang Ter (Loop).
		1989	16 January	Last bus from Jurong East Int extended to 2345 hrs daily.
			5 March	Amended to ply Bt Batok West Ave 6 and Bt Batok West Ave 3.
				Amended to ply Upp Bt Timah Rd and Bt Panjang Rd, skipping Cashew Rd.
	Bukit Merah ↔ Bukit Panjang (1990 - 2012)	1990	1 July	Integrated with Service 184, amended to start from Bt Panjang Ter and extended to Bt Merah Int.
		1995	30 April	Amended to ply Bt Batok East Ave 2, skipping Bt Batok East Ave 4.
			1 October	Operations transferred to TIBS.
		1998	TBC	First bus from Bt Panjang Ter brought forward to 0545 hrs on Sundays and Public Holidays.
		1999	26 December	Amended to Bt Panjang Int.
		2002	TBC	Skips removed bus stop opposite ITE Pasir Panjang along Telok Blangah Rd.
Template:SMRT Buses (Current)		2005	TBC	Serves new bus stop outside Hillington Green Condo along Hillview Ave, skipping the bus stop outside Hillview Hts.
		2006	TBC	Last bus from Bt Panjang Int brought forward to 2330 hrs daily.
		2010	23 May	Skips temporarily closed bus stop outside Assumption Voc Inst along Upp Bt Timah Rd to facilitate the construction of Cashew MRT station along the Downtown MRT Line.
	Bukit Merah ↔ Bt Panjang Temp Bus Pk (2012 - 2017)	2012	16 December	Amended to start from and terminate at Jelebu Rd with the opening of Bt Panjang Temp Bus Pk and the closure of Bt Panjang Int.
		2015	1 March	Serves reinstated bus stop outside Assumption Pathway Sch along Upp Bt Timah Rd.
			22 March	Designated wheelchair-accessible bus service (WAB).
			27 December	Serves additional bus stop outside Hillview Stn along Upp Bt Timah Rd.
	Bukit Merah ↔ Bukit Panjang (since 2017)	2017	4 September	Amended to Bt Panjang Integrated Transport Hub.
				Last bus from Bt Panjang Int extended to 2335 hrs daily.

Service 177 (1978 - 1988)

Operator	Year	Date	Service changes
	1978	27 November	Introduced between Bt Timah Ter and Choa Chu Kang Rd End (Loop).
	1979	30 December	Amended to ply Jln Anak Bt towards Bt Timah Ter with the partial conversion of Upp Bt Timah Rd to one-way traffic.
	1987	19 April	Serves new staggered bus stop under the PIE Flyover along Jln Anak Bt, skipping the bus stop opposite Bt Timah Plaza.
	1988	31 July	Discontinued.

Service 177 (since 1989)

Operator	Route	Year	Date	Service changes
	MINDEF Car Pk ↺ Hillview Rd (1989 - 1990)	1989	26 April	Introduced between MINDEF Car Pk and Hillview Rd (Loop) as a peak hour service on weekdays and Saturdays only.
			10 July	Morning peak trips revised to operate between 0700 and 0800 hrs.
	Bukit Batok ↺ Bukit Panjang (1990 - 1999)	1990	12 March	Extended to start from Bt Batok Int and extended to loop at Bt Panjang Ter.
			16 July	Morning peak trips from Bt Batok Int revised to operate between 0700 and 0800 hrs. Evening peak trips from Bt Batok Int revised to operate between 1615 and 1715 hrs on weekdays, and between 1200 and 1300 hrs on Saturdays.
			17 December	Evening peak trips from Bt Batok Int revised to operate between 1215 and 1315 hrs on Saturdays. Evening peak trips from Bt Panjang Ter revised to operate between 1225 and 1310 hrs on Saturdays.
		1995	2 July	Operations transferred to TIBS.
	Bukit Batok ↔ Bukit Panjang (1999 - 2012)	1999	26 December	Amended to Bt Panjang Int.
Template:SMRT Buses		2004	25 September	Revised to operate on weekdays only.
		2005	TBC	Serves new bus stop outside Hillington Green Condo along Hillview Ave, skipping the bus stop outside Hillview Hts.
		2008	TBC	Last bus (PM peak) from Bt Panjang Int revised to 1830 hrs.
			TBC	Last bus (PM peak) from Bt Batok Int revised to 1820 hrs.
		2012	1 July	Designated wheelchair-accessible bus service (WAB).
	Bukit Batok ↺ Jelebu Rd (since 2012)		16 December	Amended to loop at Jelebu Rd with the closure of Bt Panjang Int.
(Current)		2016	29 May	Operations transferred to Tower Transit Singapore.
			13 June	First bus revised to 0550 hrs (AM Peak) and 1620 hrs (PM Peak) on weekdays.
		2017	4 September	Serves the bus stop outside Blk 180 along Jelebu Rd, skipping the bus stop outside Bt Panjang Plaza.
		2020	23 November	Amended to ply non-stop along Hillview Rd and Upp Bt Timah Rd with the closure of Hillview Lk to facilitate the construction of NS Hub.
		2024	26 August	To be amended to ply non-stop along Hillview Rise with the closure of Hillview Avenue, serving the bus stop along Hillview Avenue in both directions temporarily to facilitate the construction along Hillview Avenue.

Short Trip 177A (2012 - 2016)

Operator	Year	Date	Service changes
Template:SMRT Buses	2012	17 December	Introduced from Bt Batok Int to Jelebu Rd (Bt Panjang Plaza), operating after the last bus of Service 177 during peak hours on weekdays. Wheelchair-accessible at launch.
	2016	29 May	Discontinued.

Service 178

Operator	Route	Year	Date	Service changes
	Corporation Dr ↔ Upp Bt Timah Rd (1974 - 1977)	1974	3 February	Introduced between Corporation Dr Ter and Upp Bt Timah Rd Ter under 1974 Bus Rationalisation.
		1975	9 November	Amended to realigned Jurong Rd, skipping Old Jurong Rd.
	Boon Lay Gardens ↔ Upp Bt Timah Rd (1977 - 1978)	1977	28 March	Extended to Boon Lay Gdns Ter.
	Jurong ↔ Upp Bt Timah Rd (1978 - 1980)	1978	1 June	Amended to Jurong Int and amended to ply Jurong Rd, skipping Jln Jurong Kechil.
	Jurong ↔ Woodlands Ctr (1980 - 1990)	1980	14 December	Extended to Woodlands Town Ter.
		1981	29 November	Amended to Woodlands Int.
		1983	10 July	Operations transferred to TIBS.
		1984	20 October	Amended to ply Bt Batok East Ave 3, Bt Batok St 24, Bt Batok St 23 and interim road with the partial closure of Jurong Rd (between Bt Batok East Ave 3 and Bt Batok St 23).
		1985	17 March	Amended to ply Bt Batok Rd, Bt Batok West Ave 3, Bt Batok Ctrl and Bt Batok East Ave 3 with the partial closure of Jurong Rd.
		1986	6 July	Serves new pair of bus stops outside and opposite Bt Batok Sec Sch along Bt Batok East Ave 6.
	Boon Lay ↔ Woodlands Ctr (1990 - 1996)	1990	1 July	Amended to Boon Lay Int.
	Boon Lay ↔ Woodlands (1996 - 2006)	1996	4 February	Extended to Woodlands Reg Int.
			TBC	Skips a pair of removed bus stops outside and opposite MOE Water Works along Jln Ahmad Ibrahim.
		1999	19 July	Serves new bus stop outside Woodlands CIQ along Woodlands Rd.
		2003	TBC	Serves new pair of bus stops outside and opposite Assyakirin Mque along Corporation Rd.
Template:SMRT Buses (Current)		2006	TBC	Last bus from Woodlands Reg Int brought forward to 2330 hrs daily.
			TBC	Last bus from Boon Lay Int brought forward to 2330 hrs daily.
	Boon Lay Temp Int ↔ Woodlands (2006 - 2009)		18 June	Amended to Boon Lay Temp Int.
	Boon Lay ↔ Woodlands (2009 - 2016)	2009	27 December	Amended to Boon Lay Integrated Transport Hub.
		2010	23 May	Skips temporarily closed bus stop outside Assumption Voc Inst along Upp Bt Timah Rd to facilitate the construction of Cashew MRT station along the Downtown MRT Line.
		2011	23 October	Serves new bus stop outside Intl Business Pk along Jurong Town Hall Rd.
		2013	29 September	Designated wheelchair-accessible bus service (WAB).
		2015	1 March	Serves reinstated bus stop outside Assumption Pathway Sch along Upp Bt Timah Rd.
	Boon Lay ↔ Woodlands Temp Int (2016 - 2021)	2016	12 March	Amended to Woodlands Temp Int.
			11 December	Serves new bus stop opposite Blk 635A along Woodlands Rd.
		2017	23 April	Serves relocated bus stop before PIE along Bt Batok Rd.
			28 May	Skips removed bus stop opposite Mandai Rd along Woodlands Rd.
		2018	25 March	Amended to ply Woodlands Ave 3 and Woodlands Ctr Rd towards Woodlands Temp Int.
			10 June	Serves new bus stop before Yew Tee Flyover along Woodlands Rd.
	Boon Lay ↔ Woodlands (since 2021)	2021	13 June	Amended to Woodlands Integrated Transport Hub.

Short Trip 178A

Operator	Route	Year	Date	Service changes
Template:SMRT Buses (Current)	Woodlands → Woodlands Rd (2013 - 2016)	2013	15 July	Introduced from Woodlands Reg Int to Woodlands Rd (Kranji Stn) during morning peak hours on weekdays.
			29 September	Designated wheelchair-accessible bus service (WAB).
	Woodlands Temp Int → Woodlands Rd (2016 - 2021)	2016	12 March	Amended to Woodlands Temp Int.
	Woodlands → Woodlands Rd (since 2021)	2021	13 June	Amended to Woodlands Integrated Transport Hub.

Service 179 (1974 - 1983)

Operator	Year	Date	Service changes
	1974	3 February	Introduced between Lim Chu Kang Ter and Bt Timah Ter under 1974 Bus Rationalisation.
	1978	27 November	Amended to skip Choa Chu Kang Rd End with the introduction of Service 177.
	1979	30 December	Amended to ply Jln Anak Bt towards Bt Timah Ter with the partial conversion of Upp Bt Timah Rd to one-way traffic.
	1983	27 November	Discontinued.

Service 179 (1985 - 1990)

Operator	Route	Year	Date	Service changes
	Bukit Batok ↔ New Bridge Rd (1985 - 1988)	1985	18 August	Introduced between Bt Batok Ter and New Bridge Rd Ter.
		1987	6 June	Amended to the relocated New Bridge Rd Ter.
			27 September	Amended to Bt Batok Int.
				Amended to ply the extended Eu Tong Sen St towards Bt Batok Int to facilitate the first stage of road expansion along New Bridge Rd.
			1 November	Amended to ply Eu Tong Sen St towards Bt Batok Int to facilitate the second stage of road expansion along New Bridge Rd.
		1988	20 March	Amended to ply Upp Cross St and New Bridge Rd, skipping Neil Rd.
	Choa Chu Kang ↔ New Bridge Rd (1988 - 1990)		18 December	Extended to Choa Chu Kang Ter and amended to ply Scotts Rd and Orchard Rd.
		1990	7 January	Serves new pair of bus stops outside and opposite Bt Batok Driving Ctr along Bt Batok West Ave 5.
			10 March	Extended to interim terminal along Choa Chu Kang Ave 4.
			8 April	Amended to Choa Chu Kang Int.
			16 December	Integrated with Service 190 and discontinued.

Service 179 (1993 - 1999)

Operator	Year	Date	Service changes
	1993	3 January	Introduced between Choa Chu Kang Int and Fajar Rd (Loop) under TransitLink Network Integration Exercise Phase 11.
	1995	2 July	Operations transferred to TIBS.
	1999	26 December	Discontinued under Bukit Panjang LRT Rationalisation.

Service 179 (since 2001)

Operator	Route	Year	Date	Service changes
	Boon Lay ↺ Nanyang Dr (2001 - 2006)	2001	7 January	Introduced between Boon Lay Int and Nanyang Dr (Loop).
Template:SBS Transit (Current)	Boon Lay Temp Int ↺ Nanyang Dr (2006 - 2010)	2006	18 June	Amended to Boon Lay Temp Int.
	Boon Lay ↺ Nanyang Dr (since 2010)	2010	8 May	Amended to Boon Lay Integrated Transport Hub.
		2014	7 December	Serves new bus stop opposite Blk 41 along Nanyang Dr.
		2015	3 December	Designated wheelchair-accessible bus service (WAB).

Service 179A

Operator	Route	Year	Date	Service changes
Template:SBS Transit (Current)	Boon Lay Temp Int → Nanyang Dr (AM) Nanyang Dr → Boon Lay Temp Int (PM) (2007 - 2010)	2007	1 October	Introduced from Boon Lay Temp Int to Nanyang Dr (Hall 4) during morning peak hours and from Nanyang Dr (Hall 1) to Boon Lay Temp Int during evening peak hours on weekdays, plying express sectors along Jurong West St 63 and Pioneer Rd Nth.
	Boon Lay → Nanyang Dr (AM) Boon Lay → Nanyang Dr → Boon Lay (PM) (since 2010)	2010	8 May	Amended to Boon Lay Integrated Transport Hub.
		2014	7 December	Serves new bus stop opposite Blk 41 along Nanyang Dr.
		2015	3 December	Designated wheelchair-accessible bus service (WAB).

Service 180 (April - May 1971)

Operator	Year	Date	Service changes
UBC	1971	11 April	Introduced between Bt Timah Ter and Prince Edward Ter under 1971 Bus Reorganisation.
		9 May	Integrated with Service 180A, amended to ply Stamford Rd, Waterloo St and Bras Basah Rd and re-numbered Service 180/180A.

Service 180 (1974 - 1991)

Operator	Route	Year	Date	Service changes
	Upp Bt Timah Rd ↔ Tg Pagar Rd (1974 - 1976)	1974	3 February	Re-numbered from Service 180/180A as a service between Upp Bt Timah Rd Ter and Tg Pagar Ter under 1974 Bus Rationalisation.
			8 December	Amended to ply Cecil St, skipping Robinson Rd.
		1975	19 July	Amended to ply Coleman St and Hill St, skipping Stamford Rd.
	Marsiling ↔ Tg Pagar Rd (1976 - 1979)	1976	11 January	Extended to Admiralty Rd Ter.
		1979	11 February	Amended to ply the extended Shenton Way, Rambau St and Trafalgar St towards Tg Pagar Ter, skipping Parsi Rd.
	Marsiling ↔ Anson Rd (1979 - 1985)		1 August	Amended to Anson Rd Ter.
			25 November	Amended to ply Pickering St and Church St, skipping Nth Canal Rd and Market St.
			30 December	Amended to ply Jln Anak Bt towards Anson Rd Ter with the partial conversion of Upp Bt Timah Rd to one-way traffic.
		1983	7 August	Operations transferred to TIBS.
	Marsiling ↔ World Trade Ctr (1985 - 1991)	1985	13 January	Extended to World Trade Ctr Ter.
		1990	19 August	Amended to ply Bt Timah Rd, Sungei Rd, Bencoolen St, Orchard Rd, Penang Rd and Clemenceau Ave (towards World Trade Ctr Ter) / Orchard Rd, Dhoby Ghaut, Selegie Rd and Bt Timah Rd due to the partial closure of Clemenceau Ave to facilitate Phase 2 of the construction of CTE.
		1991	6 January	Discontinued under TransitLink Network Integration Exercise Phase 1.

Service 180 (since 1996)

Operator	Route	Year	Date	Service changes
	Bukit Panjang ↔ Boon Lay (1996 - 2006)	1996	10 March	Re-numbered from Service 951 as a service between Bt Panjang Ter and Boon Lay Int under Woodlands MRT Rationalisation.
			TBC	First bus from Bt Panjang Ter brought forward to 0530 hrs daily.
		1999	26 December	Amended to Bt Panjang Int.
				First bus from Bt Panjang Int brought forward to 0520 hrs on weekdays and Saturdays.
				First bus from Boon Lay Int brought forward to 0550 hrs on weekdays and Saturdays.
Template:SMRT Buses (Current)	Bukit Panjang ↔ Boon Lay Temp Int (2006 - 2009)	2006	18 June	Amended to Boon Lay Temp Int.
	Bukit Panjang ↔ Boon Lay (2009 - 2012)	2009	27 December	Amended to Boon Lay Integrated Transport Hub.
	Boon Lay ↺ Bt Panjang Rd (2012 - 2018)	2012	16 December	Amended to loop at Petir Rd from Boon Lay Int with the closure of Bt Panjang Int.
		2017	23 April	Serves relocated bus stop before PIE along Bt Batok Rd.
			16 July	Designated wheelchair-accessible bus service (WAB).
			4 September	Serves the bus stop outside Bt Panjang Stn along Upp Bt Timah Rd, skipping the removed bus stop along Petir Rd.
	Boon Lay ↺ Bukit Panjang (since 2018)	2018	25 February	Amended to loop at Bt Panjang Int.

Service 180/180A (1971 - 1974)

Operator	Year	Date	Service changes
UBC	1971	9 May	Re-numbered from Service 180 between Bt Timah Ter and Prince Edward Ter.
	1974	3 February	Extended to Upp Bt Timah Rd Ter, extended to Tg Pagar Ter, amended to skip Stamford Rd, Waterloo St and Bras Basah Rd and re-numbered Service 180 under 1974 Bus Rationalisation.

Service 180A (1971 - 1974)

Operator	Year	Date	Service changes
UBC	1971	11 April	Introduced between Bt Timah Ter and Stamford Rd (Loop) under 1971 Bus Reorganisation.
		9 May	Integrated with Service 180 and discontinued.

Short Trip 180A (since 2012)

Operator	Year	Date	Service changes
Template:SMRT Buses (Current)	2012	16 December	Introduced from Boon Lay Int to Bt Panjang Rd (Blk 183) during evening peak hours on weekdays and after the last bus of Service 180 daily.
	2017	16 July	Designated wheelchair-accessible bus service (WAB).
		4 September	Serves the bus stop outside Bt Panjang Stn along Upp Bt Timah Rd, skipping the removed bus stop along Petir Rd.
	2018	25 February	Amended to serve Bt Panjang Int.