how long until you can apply for citizenship?

When on a work visa, how long until you can apply for citizenship? When you are applying for citizenship your visa must still be active right?

To apply for citizenship, you must have been living in the UK for at least 5 years (3 years if you are married to a British citizen). You must also have spent a year with no restrictions on your visa (it's a different visa called Indefinite Leave to Remain).

the "no restrictions" thing is only for the 5 year requirement. As a spouse, I had to have been in the country for 3 years, but the moment I had my ILR I was eligible to apply for citizenship.