Wedding guests face big bills to dance, eat cake

You don't need to be the one getting married to say "I do" to substantial wedding bills.

The average wedding guest will spend $673 per wedding this year, according to new data from American Express. That's up 13 percent from last year and 21 percent from 2013. (Tweet This.)

Scarier, that tally is just to be a regular guest—watching the couple exchange vows, enjoying some cake and (reluctantly) hitting the dance floor for the electric slide or chicken dance. Members of the wedding party are likely to spend even more.

Most of the total stems from travel costs to attend a destination wedding, or even just one that isn't in your hometown. Amex estimates guest spending at $225 for airfare (up 125 percent from last year), and $170 on a hotel (up 86 percent). (Check out the video above for some of the other cost factors that guests should consider before RSVP-ing "yes.")

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It's not the bride and groom's responsibility, per se, to consider their guests' tab in the course of planning. "We really talk to brides and grooms … about how you have these three, sometimes four factors that are really paramount to making the decisions about your wedding," said Lizzie Post, co-host of the "Awesome Etiquette" podcast. "After that, you have to let the chips fall where they may." If the couple's priority is having all their friends and family there, she said, their choices of location and other details are likely to reflect that (i.e., it's less likely to be a destination wedding or a black-tie affair that requires tuxedo and gown rental.)

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Couples prioritizing the location—be that a destination wedding in the Caribbean or their hometown in a different state—can't expect that everyone will be able to afford to attend. It's worth noting that 62 percent of consumers in the American Express survey said they don't like being forced to take a vacation to attend a wedding.

Usually brides and grooms don't bank on a big wedding in those situations, and pare down their guest list accordingly, said Alan Fields, co-author of "Bridal Bargains." Even then, it's a nice idea for the couple to wrangle room blocks at hotels with different price points to provide options for guests with limited budgets, he said.

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Guests facing high costs have plenty of avenues to explore for savings. Pull out your best travel booking tricks to track down airfare sales and inexpensive lodging, said Fields. See if you can go share a hotel room or carpool to cut costs. If the cost is just too high, it's perfectly polite to tell the couple you can't attend (or participate as an attendant) for financial reasons, said Post.

One area in which guests are spending less: gifts. The average spend is $106 if you're friends with the couple (down from $109 last year), and $142 for a family member (down from $150), according to the AmEx survey of more than 1,880 people conducted between Feb. 25 and March 3.

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"A gift should always be what's in your budget," said Post. And if your budget is less after shelling out for airfare and hotel, that's OK, too. "You can always find something that is simple and meaningful," she said. Or go in with friends for a group gift.