You may apply for this visa if you are married to a British citizen, or person who has settlement status in the UK (i.e. a person who holds indefinite leave to remain (ILR) or right of abode. The visa, which is initially issued for a 2.5 year probationary period, allows you to work without restriction and to exit and re-enter the UK multiple times. At the end of the probationary period, you will need to extend your stay in the UK for a further 2.5 years. After being on the spousal visa for a total of 5 years you must submit evidence to the Home Office that you have been living together for that time, after which you may be eligible to apply for ILR yourself.
In order to apply for this visa you and your spouse must:
Be lawfully married to one another
Intend to live together permanently as man and wife
The British citizen must meet the Financial requirement set out by the UK Visas and Immigration office.