The day my ex-husband and I combined our finances was far more significant to me than the day we got married. Marriage was a big party and a piece of paper signed by the County Recorder. Combining our bank accounts was a much bigger deal. On the day we combined our bank accounts, I knew we were making a financial commitment to each other that would be difficult to unravel if things didn't work out. And they were. Here's a few things I wish I had known before we combined our finances:

1. Taxes

If you are married on the last day of the year, you will file a joint tax return for that whole year. Even if you get married on December 31, you still file jointly for the whole year. Yes, you can file as married people filing separately, but that's not the same as filing two separate tax returns. You are still taxed as a married couple.

This could save you money or it could cost you money. Generally speaking, if you earn similar amounts of money, filing jointly will probably cost you more money. If one of you earns substantially more than the other, it could save you money.

If you are getting married near the end of the year, run out the scenarios with your CPA or using an online tax calculator and consider whether you should postpone the official marriage date until after the 1st of the year. I know that sounds weird, but if it could save you a lot on your taxes, go ahead and have the wedding, but wait to file the paperwork and make it official.

2. Combining Finances

It's not always a great idea to combine your finances right away when you get married. If you are both earning about the same amount of money and you don't have any children on the way right away, keep your own separate accounts and agree to both contribute to a joint account, which you will pay family bills from. Get used to this for a while before totally merging all of your accounts.

If one of you earns substantially less, you can adjust the contributions to the joint account pro rata. If one of you plans to quit his or her job to stay home with the kids or otherwise take care of the family obligations, make sure you've discussed ahead of time how the non-breadwinner partner will have control over some of the family money for his or her personal expenses.

No matter what, make sure you each maintain at least one account that is your own account with your own money in it that is not under the control of the other partner. Each partner needs to have their own financial autonomy even if one partner is the breadwinner and the other is not. And, each partner should have their own individual credit cards in their names.

3. Community v. Separate Property

If you live in a community property state, all of the income you earn from your labor after you are married is considered community property, which means it belongs to both of you even if it is in a bank account with just the breadwinner's name on it. Any of the property you bring into the marriage with you remains your separate property, but only so long as you maintain it as separate property and don't contribute it to the community.

If you put separate property into an account in both of your names, it becomes community property. If you earn income on your separate property and that separate property has not been gifted to the community, the income is separate.

If you inherit money while you are married, that stays separate property, but only if you keep it in its own separate account and don't mix it in with your family accounts. Once you do, it's community property.

4. Debt

Any debt you incur during your marriage, is very likely going to be debt owed by both of you, even if only one of you incurred it. Yep, it's sucky. But, true.

So, before you get married and/or combine finances, each of you should show your entire hand. Create your personal net worth statements. List out your assets and your liabilities. Then swap the information.

Keep financial records of all assets owned during the month of marriage indicating current value of all assets and amount due on all debts. This will come in handy if you end up getting divorced down the road and can save you tens of thousands of dollars in legal and accounting fees.

5. Estate Planning

Once you get married or even merely tie the financial knot, you need to get your estate plan in place. Especially if you don't have children yet, the law may not provide a default estate plan you'd be happy with. In California, half of your assets could go to your spouse and half to your parents. And, if you aren't married, your whole estate could be left to your parents, leaving your life partner out in the cold. Take the time to find out what would happen if you were incapacitated or died so you can make sure things would be as easy as possible for the one you love if anything happened to you.

Making the commitment to share a financial life with someone is a big step. Before you tie the financial knot, make sure you are on the same page about what you want out of life and how you plan to grow, preserve and spend your family wealth.