If married but living separately, can the spouse that the children don't live with claim the children if they help pay living expenses?

[Vanessa · Accepted solution]

Possibly, but only one parent can claim the children. This will depend on who they lived with the longest and if the custodial parent agrees to sign Form 8332.  

Generally, the custodial parent gets to claim the kids, however, the custodial parent can agree to allow the noncustodial parent to claim the children. If the custodial parent does not agree, then no the noncustodial parent cannot claim the kids.