[Mr-Stabby]

I randomly came across an early episode of 'Homes under the Hammer' on Freevee of all things. I knew the current title sequence had been in use a long time and assumed it was still in SD, but i didn't know that it actually has been use since at least 2003. 20 years with the same visual title sequence and theme is quite a record. Do we know of anything that has lasted even longer? Even the lower third design and font has remained the same.

[Brekkie]

Well the show is 20 years old next month (they're marking the occassion with celebrity guest hosts of all things) so I guess it's been in use since the beginning then. We're probably looking at long running daytime shows to rival it - Eggheads springs to mind which starts the same month - modified as the Eggheads have come and gone but essentially the same format, but not exactly the same.

Even the big shows all have fairly old titles - I think the I'm a Celeb titles have been in use since 2008, though of course change the celebs each year, as do Strictly (essentially the same since 2010 but with a few tweaks along the way). I think Bake Off use the same titles now on C4 as they did on the BBC.

[Robert Williams]

What about Chucklevision?  Although it was amended at various times, such as the clips at the top of the screen being updated, getting converted to widescreen and the whole sequence being sped up at one point, the title sequence introduced in the third series in 1989 remained essentially the same until it finished in 2009 - so that is once again 20 years.

www.youtube.com 

[Rdd]

Coronation Street and Eastenders come to mind - I know they’ve each been redone a few times, but in essentially the same style.

[JAS84]

Corrie's longest running title sequence lasted 14 years, 1976 to 1990, with the current one being the second longest running, 2010 to 2023 being 13 years. They introduced new opening titles in 1960, 1964, 1969, 1975, 1976, 1990, 2002, and 2010.
coronationstreet.fandom.com 

Title sequence | Coronation Street Wiki | Fandom
A title sequence is a segment of a television programme designed as an introduct…
  Source: coronationstreet.fandom.com

[JAS84]

As for EastEnders, it's current titles are the longest running at 11 years, but as you say it's not changed much since the show started.
eastenders.fandom.com 

Title and credits sequence | EastEnders Wiki | Fandom
Over the years the Eastenders Title Card has changed, below is a collection of p…
  Source: eastenders.fandom.com

[nwtv2003]

The Simpsons title sequence from 1990 to 2009 must be up there. It only changed because the show was changed to HD. Similar thinking Family Guy must also be ip there but they’ve changed some of the characters that have appeared. Notably when Brian got killed off for a few episodes.

[JAS84]

Family Guy's titles were remade for HD, replacing generic characters with the actual supporting cast in the process, but like EastEnders, it hasn't structurally changed. They also added Cleveland in Mort's place after his spin-off was cancelled and he rejoined Family Guy.

Season 1 of The Simpsons actually had a different OP, but with the same structure as the other two versions. The biggest difference being the bus stop scene, as Bart steals the sign and the queue waiting ends up chasing a bus that fails to stop, instead of the later two versions which both involve Bart skateboarding around obstacles (including generic characters in the 1991 version, actual supporting cast in the HD one).

[Dadeki]

Only Fools and Horses were still using the original 1981 sequence by the time of the 2001-03 Christmas specials (although the photographs of the cast were updated). Of course, the original 1981 series used a different theme tune although this was replaced by the second series (and subsequent showings of the first series) with the now iconic theme.

From the 1996 Christmas special: 
www.youtube.com 

[Stooky Bill]

Parts of the titles of The Graham Norton Show are very old, even including a 4:3 CRT telly.

youtu.be 

It does have a different logo now and they've removed the rather young looking Graham
youtu.be