Former UK prime minister Sir Keir Starmer has announced he will stand down as MP for Holborn and St Pancras after 11 years in Parliament, triggering a closely watched by-election in north London.
It has been an honour and a privilege to represent Holborn and St Pancras for the last 11 years.
— Keir Starmer (@Keir_Starmer) September 1, 2026
My statement. pic.twitter.com/xzu4xcIno2
Starmer announced his decision on Tuesday, September 1, following weeks of speculation over whether he would remain in the House of Commons after leaving Downing Street earlier this summer.
The decision represents a change from Starmer’s position in July, when he indicated that he planned to remain an MP until the next general election. He has now decided the time is right to leave Parliament and concentrate on work outside Westminster.
His departure comes only weeks after Andy Burnham replaced him as prime minister and Labour leader, making the coming Holborn and St Pancras by-election an early electoral test for the new government.
The announcement also lands on a significant day at Westminster, with Burnham making his first Commons appearance as prime minister.
Why is Keir Starmer standing down as an MP?
Starmer explained his decision in an interview with the Camden New Journal, the local newspaper covering his constituency.
The former prime minister said he had reflected on his future after leaving Downing Street and believed it was the right moment to “pass the baton to a successor”.
Starmer described representing Holborn and St Pancras as a major honour and said his next chapter would focus heavily on international affairs.
He identified defence, security, trade and technology as areas in which he intends to work as he moves beyond frontline parliamentary politics.
Starmer also said he intends to continue his longstanding work on combating violence against women and girls, an issue he worked on before becoming an MP.
“I will now focus on other things and that will be international affairs including defence, security, trade and technology in a fast-changing world,” Starmer told the Camden New Journal.
Starmer entered Parliament in 2015, succeeding former Labour cabinet minister Frank Dobson as MP for Holborn and St Pancras.
He went on to become Labour leader in 2020 before leading the party to a landslide victory at the 2024 general election and entering Downing Street as prime minister.
Starmer has also highlighted his constituency record as he prepares to leave Parliament, pointing to work involving affordable housing, education, youth support and measures affecting families and renters.
His departure marks another major development during a fast-moving period in UK politics. Britain has also faced several other major national stories in recent weeks, including a UK airport cyber attack affecting millions of customers.
Holborn and St Pancras by-election: What happens next?
Starmer’s departure will trigger a by-election in Holborn and St Pancras, although a polling date has not yet been announced.
The seat has traditionally been a Labour stronghold and has been represented by Starmer since 2015.
At the 2024 general election, Starmer received 18,884 votes, or 48.9% of the vote. He retained the constituency with a majority of 11,572 votes.
Independent candidate Andrew Feinstein finished second with 7,312 votes, while Green candidate David Stansell came third with 4,030 votes.
Those results mean Labour enters the coming contest from a strong position, but the circumstances surrounding the former prime minister’s departure could turn what would normally be a relatively safe Labour seat into a nationally watched political battle.
Attention is already turning to who could contest the seat.
The Green Party has not ruled out leader Zack Polanski standing in the by-election. A party spokesperson said following Starmer’s announcement that Polanski has previously made clear that he would like to become a London MP.
Polanski is currently a member of the London Assembly. A run in Holborn and St Pancras would give the Green leader an opportunity to seek a seat in the House of Commons.
Andrew Feinstein could also be a figure to watch after his second-place finish against Starmer in 2024, although the full candidate list has not yet been confirmed.
Labour, meanwhile, will have to choose a new candidate to defend the constituency.
Starmer has indicated that he does not intend to publicly endorse anyone during the Labour selection process. He has said he will instead support whoever is ultimately selected by the party.
The contest will be particularly significant for Prime Minister Andy Burnham. As one of the first major electoral tests since he replaced Starmer, the result could offer an early indication of how voters are responding to the new Labour leadership.
The Conservatives have already criticised Starmer’s decision to leave Parliament after his earlier pledge to remain an MP.
Conservative Party chairman Kevin Hollinrake described the decision as another change of position while saying he wished Starmer and his family well for the future.
The political contest will add further attention to north London, which has recently been at the centre of other major breaking stories, including the major fire near Wembley Stadium.
Starmer’s departure also puts him among former prime ministers who chose to leave the Commons relatively soon after leaving Downing Street.
Boris Johnson and David Cameron both left Parliament after their premierships, while others remained MPs for longer. Theresa May, for example, continued as an MP for several years after leaving No 10.
For Starmer, attention will now shift away from Westminster and towards his planned work on international affairs.
Exactly what position he could take has not yet been announced. However, his emphasis on defence, security, international trade and technology provides the clearest indication so far of where his post-political career could be heading.
For voters in Holborn and St Pancras, the immediate questions are more straightforward: when will the by-election take place, who will Labour select, and which challengers will enter the race?
Those details are expected to become clearer as the process to replace the former prime minister gets underway.
Developing story: This article will be updated as the Holborn and St Pancras by-election date, Labour candidate and other confirmed candidates are announced.
Make Swikblog your go-to source on Google for reliable updates, smart insights, and daily trends.
