The biggie. The one variable that will drive every other cost. Follow the rule of thirds, be a jerk, and use a police lineup. Here’s how.

Your wedding’s guest list is like the world’s supply of crude oil. Its supply and demand will drive every other cost of the global economy (your wedding); it’s contested by every superpower (the bride, the mothers), and it will trigger wars and bloodshed (your fights with the in-laws).

This is it. The biggie. As we’ve mentioned before, the size of your guest list is the one variable that will make or break your wedding’s budget. A few extra guests could mean the difference between an open bar and boxed wine.

Our overriding principle: don’t be afraid to be a jerk. No, not to your family and fiancée, but to any friends you’re worried about inviting. Think of it this way. When you’re not sure if you want to invite a friend, just don’t invite them. It’s that simple.

More specifically, stick to these 10 guidelines:

1. Follow the Rule of Thirds.

Simple, clean, fair, battle-tested. A third of the guests for your family, a third of the guests for her family, and then a third of the guests for your (and her) friends. Will it work out that neatly? Nope, but it’s a good place to start and a tidy, objective method for avoiding tug-of-wars. Obviously this gets more complicated when one family is footing 99% of the bill. Theoretically the rule still applies (according to conventional etiquette), but if the Paying-Family wants to fork over even more money to invite more guests, fine, as long as they’re not shafting the non-payers (i.e. Payers have 100 guests, Non-Payers have 20.) For more on the wedding’s cruel relationship between money and power, click here.

2. Diss your co-workers.

You see these losers enough Monday through Friday. Dump ‘em. All of them; you can’t just invite half your team and ignore the rest. Ditto for your boss. Click here for more on this topic, but unless you work in a crassly political office where everyone sucks up and invites their boss, just abandon the entire lot. How do you get away with this? Next rule.

3. Lie.

It’s what makes the world go ‘round. You must lie, lie, lie. Even on a lavish budget, some people will be snubbed and some feelings will be bruised. You must lie. Consider what the truth would sound like:

“Hey there. I know that you think we have a friendship. And we sort of do…barely. And, sometimes—not often, but every now and then—I enjoy your company. But here’s the deal; my cube is next to your cube. That’s it. If I invite you to my wedding, that will cost me another $100, and that means I’ll need to invite Ted and Sarah and Josh, and I hate those bastards even more than I dislike you. No hard feelings, right?"

Lie. Use two sets of bullshit buzzwords. Just tell them that you’re having a small wedding with only friends of the family. “Friends of the family,” in particular, is a lethal weapon of diplomacy. Chances are these jerk-offs haven’t met anyone in your family so they won’t feel insulted. And make a deal with your fiancée. For the purposes of white lies, you should blame her and she should blame you. Seriously. Back to your co-workers, just tell them, “Ahhww, man. I’d love to invite you. But Sarah made me agree to a strict ‘no co-workers’ policy. Sorry dude.”

For more half-truths, white lies, and other canned “clichés” you should have in your hip pocket, click here.

4. No COGs.

Some wedding-porn suggests that since the ceremony and the reception, technically, are two different events, you can lower costs by inviting some guests just to the ceremony and some lucky-ass VIPs to both events. We’ll give you the courtesy of candor: doing that makes you a dick. It’s awkward and classless. What are your COGs (ceremony only guests) going to do after the bride kisses the groom? Go to a different bar by themselves? Lame.

If you can’t afford to invite someone to the reception, never invite them to the ceremony. It will look like you’re trolling for gifts. The reverse, however, is not true. If you’re getting married in a chapel the size of a meat locker, it’s fine to invite a larger crowd to the reception. I hate to break this to you, but outside of your families and a few unbalanced women, no one gives a rat’s ass about the ceremony itself.

5. Ground the kids.

Easy rule of thumb. Unless they’re immediate family, never invite anyone who hasn’t hit puberty. For more on this, click here.

6. No Maury-Friends.

You know Maury. He’s your annoying friend-of-a-friend from college that borrowed $20 and never gave it back. You haven’t seen him in years. Sometimes he forwards you dumb e-mails. On Facebook he throws “virtual snowballs” at you. Cut him loose. And keep perspective. For every Maury you reject, that gives you another $100 that you can splurge on booze for people you actually like.

7. Tolerate the tools.

On the other hand… you’re not going to like everyone at your wedding. Deal with it. Some people simply have to be invited—annoying cousins, your mother’s best-friend-slash-yoga-instructor, and your bride’s father. Resign yourself to the fact that you’d be secretly, evilly, genuinely happy if 10% of your guests were hit by a bus. This is normal.

8. Limit(?) the Plus Ones.

This one’s tough. It’s the grayest of all the gray areas. According to tradition—which gets less and less relevant by the second—guests only bring a significant other if they’re actually married. Now the more common rule of thumb is if they’re living together. One (sensibile) rule of thumb is that if you've never actually met the date, then you don't need to invite them. Our take? By getting more ruthless elsewhere (co-workers, friends who aren’t really friends, little brats) you’ll be able to be more generous with the plus-ones. Remember, you want your guests to have a relaxed good time, not to get drunk and rush out to a booty call…

9. Involve the parents.

We know, we know, this is pretty damn obvious if they’re paying for the wedding; of course they’ll be involved. But if you’re the ones footing the bill, it might be tempting to bypass Mom and Dad. Don’t. After the bride, this matters more to the mothers than anyone else; make sure you get their input and preferences. Even beyond the scope of “wedding planning,” it’s just being a good(ish) son.

10. Use a Police Lineup.

When my sister got engaged, she agonized over whether to invite Mr. Peterson, an old friend of my father’s. He (my father) asked her if she could recognize Mr. Peterson out of a police lineup. She said she couldn’t. My father said, “Then if you can’t even recognize the guy out of a police lineup, why would you want him at your wedding?” So Mr. Peterson wasn’t invited. No, your parents might not be that reasonable or flexible. But if they are, or if you simply need a compelling way to phrase your objections, the “police lineup” is proven and reliable.

Want a good tool for the guest list management? We've got you covered. Use The Plunge's Badass Guest List Spreadsheet. It's the best in the business, bar none.

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