Unmarried Partner - documentation

I will be applying for a tier 2 visa with my boyfriend as an unmarried partner.  We've been living together for a little over 3 years.  What sort of documentation do you recommend to include in the application?  We have both our names on our leases but do not have a joint bank account.  The only bills we have with both our names is the renter's insurance, everything else is either in his name or mine.  Will the lease agreement and renters insurance be enough?  I feel like I should include as much as we can, but like I said, bills are either in my name or his, generally not both. 

Thanks for any advice!!!     
Michelle

You don't need all joint documents.  Anything which shows you living at the same address will do.

Vicky

These are the instructions ECOs are given in assessing unmarried partnerships (emphasis mine):

The parties having been living together in a relationship akin to marriage/civil partnership which has subsisted for two years or more.
"Living together", should be applied fairly tightly, in that we would expect a couple to show evidence of cohabitation in the preceding 2 year period. Periods apart would be acceptable for good reasons, such as work commitments, or looking after a relative which takes one partner away for up to 6 months where it was not possible for the other partner to accompany and it can be seen that the relationship continued throughout that period by visits, letters etc. Where a couple have been living together for the preceding 2-year period but have been dividing their time between countries and may, for example, have used the "visitor" category, then this will be sufficient to meet the requirement.

"Akin to marriage or civil partnership", is a relationship that is similar in its nature to a marriage or civil partnership which would include both unmarried and same-sex relationships.

In order to demonstrate a 2-year relationship evidence of cohabitation will be needed. In order to show a relationship akin to marriage/civil partnership, ECOs should look for evidence of a committed relationship. The following types of evidence would be useful in this respect:

joint commitments, (such as joint bank accounts, investments, rent agreements, mortgage, death benefit etc);
if there are children of the relationship, a record of their birth entry;
correspondence which links them to the same address;
any official records of their address (e.g. Council Tax, Doctors records, DWP record, national insurance record etc);
any other evidence that adequately demonstrates their commitment to each other.
It will not be necessary to provide all of the above: ECOs are looking for satisfactory evidence of relationship.

As Vicky has already said, you don't need everything to be joint. Indeed, per the guidance,  you don't need anything to be joint, but it can help the ECO.