Beginnings

The NSP was founded by a group of middle-class businessmen and women on 6 March 1987. The founding president and secretary-general of the party were Kum Teng Hock and Soon Kia Seng respectively. Kum was a former member of the ruling People's Action Party (PAP) while Soon was the ex-chairman of the Singapore Democratic Party.^[1]

According to its 1995 manifesto, the main political objective of the NSP was to organise and maintain a democratic movement that would ensure the solidarity and establishment of a just political system and standard of living. The party believed in a multi-party political system so that the rights and interests of the people could be proportionately represented. The NSP also aimed to establish an open and freely competitive economic environment that would provide sufficient opportunities for local enterprises. Today, the NSP continues to strive for these values. It continues to promote the establishment of a multi-party political system as well as a pro-business economic environment.

NSP made their political debut in the 1988 general election, and has contested in every election since. NSP also had contested in the 1992 by-election for the constituency of Marine Parade GRC, which was led by then-Prime Minister Goh Chok Tong.

As member of Singapore Democratic Alliance

Ahead of the 2001 general election, the NSP became a founding member of the Singapore Democratic Alliance (SDA), along with the Singapore Justice Party (SJP), the Singapore People's Party (SPP) and the Singapore Malay National Organization (PKMS). The Chairman of the alliance was the SPP leader and then-Member of Parliament (MP) for Potong Pasir, Chiam See Tong (who was the SDA's only candidate-elect until 2011).

On the polling day, the party's then-secretary General Steve Chia, who contested the Chua Chu Kang Single Member Constituency but defeated with a vote share of 34.6%, was the highest percentage secured by a losing opposition candidate at the election, and Chia assumed his Non-Constituency Member of Parliament (NCMP) post, becoming the first non-Workers' Party (WP) NCMP to do so.

However, despite Chia losing his election but increased his margin to 39.63% in the 2006 general election, he lost his position as a NCMP and did not return to Parliament (the highest percentage among losing candidates was for the WP team of Aljunied GRC at 43.9%; party's chairman Sylvia Lim succeeded Chia for the NCMP role).

Party rebuild and the 2011 general election

In 2007, the NSP decided to withdraw from the SDA^[2] with a view to "explore new possibilities through wider latitude to manoeuvre, re-engineer, and rebuild the NSP". Sebastian Teo also took over the leadership of the party from Steve Chia. The party acquired a new collective colour of orange for their activity jersey as a sign of vitality, rebirth and unity, and the newsletter underwent a transformation and adopted the new name North Star.

In the 2011 election, the party fielded the most candidates of all Opposition parties for the election, with 24 candidates contesting in four Group Representation Constituencies (Chua Chu Kang GRC, Jurong GRC, Marine Parade GRC and Tampines GRC), and four Single Member Constituencies (Mountbatten SMC, Pioneer SMC, Radin Mas SMC and Whampoa SMC; the latter was currently defunct). This election saw a boost in electoral support for the NSP, notably receiving endorsement from the newly formed Reform Party along their supporters. The party was led by then Secretary-General Goh Meng Seng (a former WP candidate, and currently the leader for People's Power Party), and saw introductions to prominent candidates, which include Nicole Seah, Hazel Poa, Tony Tan Lay Thiam and Jeanette Chong-Aruldoss.

However, despite fielding notable candidates such as former MP Cheo Chai Chen and entrepreneur Hazel Poa, the undefinable branding took a huge toll on the party by a lack of a strong party brand, as the party was defeated in all eight of the contested constituencies; Goh resigned from his post shortly after the election.

General Election 2015

The party expressed intention to contest five constituencies (MacPherson, Marine Parade, Pioneer, Sembawang and Tampines), but the party shortly dropped out on MacPherson and Marine Parade, citing the possibility of multi-cornered contests that were likely to dilute the votes from the incumbent opposition WP and reducing the chance for a more diverse Parliament.^[3]

The party later changed their mind a few days later, and announced their intention to contest MacPherson SMC citing closeness with the constituency as they had contested there in the prior election. In a response, a few party members, such as acting secretary-general Hazel Poa^[4] and a CEC member Fazli Talip,^[5] resigned from NSP, citing that they were strongly opposed on a very controversial decision to contest MacPherson. The party initially fielded Chia as the candidate, but he later withdrew on 23 August due to the online abuse that received from him,^[6] and the party eventually chose Cheo as a candidate. Prior to the election, few members had earlier resigned, which members include Nicole Seah and Jeanette Chong-Aruldoss, who later joined WP and SPP, respectively.

During the campaigning period, Cheo drew public outcry on an interview citing MacPherson's incumbent Tin Pei Ling's status as a new mother was "her weakness" and saying that she might spend more time focusing on her child than on her constituents, and later claimed it as a joke.^[7] On 8 September, Tampines GRC candidate Choong Hon Heng's rally on booing PAP had gone viral.^{[8][lower-alpha 1]}

The party failed to win any of the constituencies, and Cheo had his S$14,500 electoral deposit forfeited as a consequence of garnering less than 12.5% of the valid votes cast for MacPherson (215 or 0.82%).^[9]

Earlier, Lim Tean was appointed as acting-secretary general following Poa's resignation, but resigned from his post and left NSP in May 2017,^[10] and formed his new party, Peoples Voice, in October 2018.^[11]

General election 2020

The party fielded a total of 10 candidates and contested Sembawang and Tampines in the 2020 elections. The party also expressed interest in contesting MacPherson and Pioneer, but both withdrew and respectively backed the People's Power Party^[12] and Progress Singapore Party.^[13] Ahead of elections, Steve Chia also resigned from NSP and participated the Singapore People's Party and became the new secretary-general a year later.^[14][15]

On polling day on 10 July, the party neither won any GRCs, but improved their both shares for popular vote and overall vote share by 25.27% and 3.53% to 33.15% and 3.76%, respectively. Former NSP and now-PSP member Hazel Poa however fell short on being elected in the West Coast GRC (whose team led by former PAP MP and 2011 presidential candidate Tan Cheng Bock) in about a 4% margin, but by-virtue on having the best performing result among losing candidates, Poa became a Non-constituency Member of Parliament along with Leong Mun Wai.^[16]

List of secretaries-general

19th Central Executive Council

Parliamentary elections

Due to a merger with the Singapore Democratic Alliance in the 2001 and 2006 elections, the number of candidates represented by the National Solidarity Party was displayed in parentheses; the number of elected seats represented shown first was for the National Solidarity Party, and the next by SDA.

Election	Seats up for election	Seats contested by party	Seats won by walkover	Contested seats won	Contested seats lost	Total seats won	Change	Total votes	Share of votes	Popular vote	Resulting Government	Leader
1988	81	8	0	0	8	0 / 81		50,432	34.6%	3.8%	No seats	Kum Teng Hock
1991	81	8	0	0	8	0 / 81		57,306	37.1%	7.3%	No seats	Rasiah Thiagarajah
1997	83	7	0	0	7	0 / 83		48,322	30.1%	6.7%	No seats	Tan Chee Kien
2001	84	13 (9)	0	1 (0)1	11 (11)1	0 / 84 1 1 / 84	1	75,428	27.6%	12.0%	Largest Opposition (+1 NCMP)1	Chiam See Tong (SDA)
2006	84	20 (11)	0	1 (0)	19 (11)	0 / 84 1 / 84		145,628	32.5%	13.0%	Opposition
2011	87	24	0	0	24	0 / 87	1	244,682	39.25%	12.04%	No seats	Goh Meng Seng
2015	89	12	0	0	12	0 / 89		79,780	25.27%	3.53%	No seats	Lim Tean
2020	93	10	0	0	10	0 / 93		93,546	33.15%	3.76%	No seats	Spencer Ng

Parliamentary By-elections