Relationships are tough. Joint checking accounts are even tougher! If you are in a relationship that aspires to co-mingling of your financial assets, consider setting up a budget. And if you value your sanity, a set of books, too! Here are some suggestions for retaining said sanity:
Pick A Role
You both need responsibilities. One of you might be in charge of buying food. The other, the utilities. One might feel more comfortable wrestling with the mortgage, insurance and property taxes. The other, perhaps the household supplies and clothing portion of the budget. The point is - SPECIALIZE! If you do, you can become proficient in your own area of the budget, and both of you will benefit.
Reporting and Review
A budget is completely meaningless unless you do what you are supposed to with it:
Compare it to actual spending
This comparison effort must be immediately following the period in question. Each week, or each month, sit down and see how you are doing. In general, you'll know instinctively if you've gone over. It tends to show in your checking account. Open a dialog about how the reporting period went, and how you can improve your performance during the next period. Discuss strategies and priorities. Also, any unique challenges the next period might hold. It's far better to get the tough stuff out in the open in advance, than to deal with the consequences after it happens. You might even manage to resolve it ahead of time.
Limit your use of lending and credit.
Credit cards are a great way of tracking your expenses. Properly used, they can also build credit. The problem is, the spending can get away from you. Here's a trick: use both credit and debit cards. Make a firm commitment to put all significant purchases on your debit card. Leave the token purchases to the credit card, and keep the balances current, and low, thus establishing and enhancing your credit score while at the same time, avoiding any signficant consumer debt.
Salt the savings away for good.
When you go under budget for any period, transfer the excess funds to an account that will go into your major investment programs - kid's education, retirement funds, whatever. Don't leave it lying around to be swallowed up by the next month's largesse. Take advantage of it!
Keep a sense of humor and be flexible
We're all human. We make mistakes. Life is way way too short to spend arguing over money all the time. If your partner has trouble getting with the program, consider a couple of options:
1. Take over all the finances. This is a common practice. The one with the money smarts just controls 100% of the finances. It's not very satisfying or enlightening to the non-engaged partner, but it works. At least until there is a separation (by divorce or death, for example) Then the non-involved partner is back to square one.
2. Get some counseling. Sometimes this means marital counseling. Other times, it's just some financial education. Understanding the big picture.
Don't overlook goal-setting and dreambuilding in all this. It's vastly easier to keep to a budget if you know where your finances (and your lifestyle) is headed as a result.