New mortgage

[sirmione16]

Me and my partner have a joint mortgage. If we split up, sell the house and divide the proceeds - when looking to buy, am I now effectively a "first time buyer"?

Probably not.
Terms and conditions for each broker can vary, but I wouldn't expect to be considered a FTB in that situation. But you might get lucky.

Assume you're talking about stamp duty rather than mortgage products? In which case no you wouldn't be a FTB.

Certainly not for stamp duty purposes. My partner owned with his ex, when they split he signed the house over to her; he didn't count as a first-time buyer when we bought, even though he had no 'proceeds' from his former house.

From gov.uk:
"A first time buyer is defined as an individual or individuals who have never owned an interest in a residential property in the United Kingdom or anywhere else in the world and who intends to occupy the property as their main residence."

Thanks all :)