Start with Percentages

After you determine the venue and the number of guests you can afford, assign 50 percent of that number to the bride and groom and 25 percent to each set of parents (or, with multiple sets of parents, 25 percent to each side altogether), suggests Anna Post, author of the forthcoming Do I Have to Wear White? Emily Post Answers America’s Top Wedding Questions (Collins, $15, amazon.com). If your parents are paying for the wedding, you may want to give them a higher percentage. If it turns out that one of you doesn’t need all your allotted spots, you can redistribute them to whoever has requested more.

Give Parents Their Number Early

To save embarrassment later, give them specific guidelines as soon as possible―before they start making phone calls inviting friends and family, suggests Sharon Naylor, author of 1001 Ways To Save Money . . . and Still Have a Dazzling Wedding (McGraw Hill, $17, amazon.com).

Create Tiers

Once you have written out a draft of your complete list, place each guest into a relationship category, Naylor says. The first tier consists of essential family members (grandparents, siblings, uncles, first cousins); the second is close friends and extended family (second cousins); the third is colleagues and other friends. When you know how many guests you can afford, start cutting the list from the bottom tier up. You’ll save potential hurt feelings by eliminating entire groups of people (say coworkers or your book club), rather than inviting just a few. That said, if someone’s truly important to you, of course you should ask him.

Do the One-Year Test

If you’re not sure whether to invite someone, “Ask yourself, ‘Have I seen or spoken to this person in the last year?’” says David Tutera, celebrity event planner and host of the TV show My Fair Wedding. “If the answer is no, odds are that you can keep them off your must-have list.”

Selectively Offer Invites with Guests

“One thing that often trips up brides is whether to give ‘plus guest’ on the invitation,” says Naylor. Her solution is to do so only when you have socialized with the couple. If someone asks if he or she can bring a guest, diplomatically tell them that this is how you made the difficult decision; that there will be a lot of other singles going without partners; and that, for budget reasons, you had to eliminate a lot of family and colleagues, “which should make them feel special that they themselves were invited,” says Naylor.

Consider Having a Small Wedding

Perhaps the easiest way to offending people while keeping your numbers manageable, says Tutera, is to keep your wedding day to family and close friends only. Then, when you’re back from your honeymoon, have a large cocktail party and invite everyone.