To qualify and get the UK Spouse Visa , both resident and the applicant who wants to join must fulfil some criteria set by the immigration authorities.
The eligibility criterias are as follows:
The person who you want to join should be a British citizen.
Your marriage must be recognised in the UK.
You have to prove you will marry in 6 months if you are a fiance.
You should have a two years of relationship before you apply for this. This is to prevent arranged marriage which is not recognised in British law.
Financial requirements must be fulfilled by the partner living in the UK.
Should have passed the English language test.