In 'The Simpsons' how long have Homer and Marge been married?

I don't think their wedding date was ever specifically mentioned, but in the 'I Married Marge' episode, Homer mentions the beginning of the 80's, and there are references to John Anderson, The Empire Strikes Back and other things that would make it around 1980 or 1981.

https://en.wikipedia.org/wiki/I_Married_Marge#:~:text=%22I%20Married%20Marge%22%20is%20the%20eleventh%20episode%20of,be%20pregnant%20again%20and%20visits%20Dr.%20Hibbert%27s%20office.

This says 1981 after Homer got Marge pregnant in 1980 (satguru, moderator)

In an episode (can't remember its name) Marge and Homer went to visit Dr Hibbert, and he told Marge that she was pregnant. At this point Marge and Homer weren't married. They only got married a couple of months before Bart was born, so if Bart is 10 years old (as he is) that means that Marge and Homer have been married for a maximum of 11 years.