UK passport

The spouse would first need to apply and obtain UK citizenship:
https://www.gov.uk/apply-citizenship-spouse

To be naturalised as a British citizen they would have had to be resident in the UK for at least three years (rather than the standard five years) prior to application.

Thank you Simon and Laura. I should have checked their site ahead of my question, but you both were correct. I needed to be phyically living in the UK for three years prior to application. Yak!
Thank you again
Sara Y

Being married to a UK citizen doesn’t automatically mean you can get a UK passport. The spouse would first need to become a British citizen themselves before they can apply for a passport.

Usually that involves living in the UK for a number of years, getting permanent/settled status, and then applying for citizenship. Once citizenship is approved, getting a UK passport is fairly straightforward.

So in short: marriage alone doesn’t qualify someone for a UK passport, but it can make them eligible to apply for British citizenship sooner than other applicants.