Whether you're throwing a celebration that's bare-bones or blowout, here's how Washington, D.C.-area planner Carol Marino, of A Perfect Wedding in Fairfax, Virginia, suggests divvying up your budget. Just remember to include sales tax in your calculations.

Reception (Food, Beverages, Rentals, and Site): 40 percent to 50 percent

Flowers: 10 percent

Photography/Videography: 10 percent

Bride's and groom's attire: 5 percent to 10 percent

Music: 5 percent to 10 percent

Planner or Coordinator: 10 percent to 15 percent

Miscellaneous (Favors, Transportation, Etc.): 10 percent

Cushion: 5 percent to 15 percent

1. Never—and we mean never—go into debt to pay for a wedding. Instead, consider throwing an intimate gathering and put off the big reception until you've saved up for it.

2. Don't charge your wedding bills unless you can pay off the balance in full as soon as you get each statement. Credit-card interest rates and finance charges can add hundreds, even thousands, of dollars to your bill, even if you carry a balance for only a month or two.

3. Don't agree to any upgrades (colored table linens, fancy chair covers) without first asking if they cost extra.

4. Don't spend more than you'd planned in one area unless you can cut that cost in another area.

5. Don't budget for fewer guests than you invited. It's better to overestimate.

To arrive at a realistic budget, start by researching the price of weddings in your specific area. The average varies wildly across the country—from around $20,000 in Little Rock, Arkansas, to $75,000-plus in the ritzy suburbs of Chicago. At Cost of Wedding, you can enter your ZIP code and get a snapshot of costs in your area. For budget-cutting ideas check out our 65 Ways to Trim Your Budget.

If you have your heart set on a specific site, florist, or band, call that vendor to get a sense of their fees. During this preliminary planning stage, you'll also need a ballpark figure for the number of guests you'd like to invite. All this early deliberation and fact-finding will give you a more accurate estimate of how much your fantasy wedding will cost.

Armed with this information, it's time for you and your fiance to have an open, respectful talk about how much you can actually afford. Whether to include others in this conversation depends on who will be contributing to the wedding. Though more and more couples are paying their own way it's still common for the bride's and groom's parents to take care of at least some of the expenses. If your families are willing to open their checkbooks, it's crucial to get their input up front, and to be mindful of your hosts' limits and gracious about their choices.

Once you've settled on a hard number, the next step is setting your top priorities. Perhaps your top priority is a gourmet dinner, a breathtaking location, or mind-blowing live music. Once you can determine that, it will tell you where you should put most of your budget. Keep in mind that you and your groom may not agree on what's most important, so you'll both need to come to an understanding.

As couples often find, your dreams may be far bigger than your pocketbook, and you'll need to cut back your expectations. Although it's always tough to realize you can't have everything, there are all kinds of creative ways of saving money that don't look like you're saving money. Some of them are sneaky and simple, like cutting down on the number of tables at your reception, which translates into fewer expensive centerpieces. Some of them aren't quite so pain-free.

Remaining within your budget also means staying organized. Track your expenditures by saving receipts and recording your spending. Our interactive budget planner can help you get a handle on your finances. File copies of every vendor estimate in a folder so you can refer to them if need be. And remember to keep a cool head and just say no to things you can't afford.