This is what I had for my appointment last week which is fairly accurate and you mustn't miss one.
- Email confirming appointment payment and time/date
- Email with IHS reference number on
- Email confirming IHS payment
- Applicant's Passport
- Sponsor's Passport
- Applicant passport photograph (x2)
- Sponsor passport photograph (x1)
- Marriage Certificate
- 6 of latest payslips
- Employer letter
- Bank statement (printed and stamped on each page)
- Council tax bill (shared)
- Water bill (shared)
- Water bill (shared)
- Work Income Protection Letter (applicant)
- HMRC Tax Calculation Letter (applicant)
- NHS Appointment letter (applicant)
- Home Insurance letter (sponsor)
- Bank Statement (sponsor)
- Council Tax Letter (sponsor)
- Tenancy Agreement
The items in bold....you need either 6 items with both your names on spread over the last two years, or, where you don't have shared items, you need an item each for that same period.
So you'll need (either shared or one each) items with your address on from periods:
Feb-Jun 2015
July-Oct 2015
Nov-Jan 2015/16
Feb-Jun 2016
July-Oct 2016
Nov-Jan 2016/17
You mustn't miss a period or at least have a very valid reason to miss one (eg. lived with parents so never got a bill). If you did live with parents you would need a letter saying that you lived there.
As it's the beginning of February remember to get your latest bank statements and payslips (assuming your spouse gets paid at the end of the month).