Although many of the issues faced by unmarried couples living together are very different from those that married couples face, the issues surrounding the sharing of expenses is common to both.

While the actual method you decide on for sharing expenses may be unimportant, to avoid disagreements later you should discuss up-front how you want to handle this issue. Will you divide housing costs and day-to-day expenses equally or contribute to a household fund in proportion to your income? The latter may be the fairest method if one of you earns significantly more than the other. For example, let's say one of you makes $40,000 per year and the other makes $20,000. The one that makes twice as much will contribute $2 for every $1 the other contributes to the joint household fund.

What will your banking arrangements be? Will you share a checking account, deposit both your checks into it, and pay all your household bills from it, or will you maintain separate accounts and settle up with each other as bills come in? If you choose to maintain separate accounts, it's a good idea to document your intention to share expenses by paying your portion of bills directly rather than paying your partner your share in cash or by check. This documents the implied contract (mentioned previously) and could protect you if your relationship ends in court. If you decide to have a joint bank account, be aware that either of you could legally take all the money out of the account. Many people have ended a live-in relationship by walking away with the cash and leaving their partner high and dry. It's safer to keep separate bank accounts, especially in the early years of your relationship.