It can be fun watching a friend blow out the candles on their birthday cake, but depending on how they choose to celebrate, you might feel like you're blowing your last dollar, too.

Over 80% of Americans say they tend to celebrate their birthday with a special meal, including 40% who say they do so every year, according to a 2023 survey from YouGov. When it comes to my friends, a special meal often means a fancy restaurant dinner.

As a college student living on part-time wages, I often find these celebrations hard to fit in my budget, but I usually suck up the cost out of fear of ruining a friendship.

While I don't regret those experiences, expensive outings that feel mandatory can breed resentment between friends, says Elaine Swann, an etiquette expert and founder of Swann School of Protocol. "It can cause a bit of angst, and part of it is our lack of communication," she says. "This is why I really encourage people to be honest with whatever your position is and then approach it in a respectful manner."

Here are the two ways etiquette experts say you can celebrate your friends without compromising your budget.

1. Only order what you can afford

If the restaurant that your friend is eyeing is too expensive for you, you can eat beforehand and order an appetizer as your meal, says Diane Gottsman, etiquette expert and owner of The Protocol School of Texas.

"When you get there, you say, 'I love their brisket. Here, I'm just going to get the brisket. This is going to be my meal,'" Gottsman tells CNBC Make It. "So, it doesn't make you look cheap. You spin it to where it's comfortable for you."

Alternatively, showing up after the appetizer and main course to catch the end of the celebration can help keep your expenses more reasonable, says Lizzie Post of The Emily Post Institute.

If that's your plan, you might tell the host, "'Hey, I can't be there for the whole dinner, but I could get there by time for dessert, and I'm happy to contribute to that,'" Post says. "That just helps you both participate, but probably participate at a less expensive level."

2. Suggest a one-on-one celebration instead

Sometimes, no matter what you plan to order, a restaurant is simply out of your price range. If money is tight, it's fine to gracefully bow out and circle back another day, Swann says.

After all, "the invitation is a question as to whether or not you can attend," she says. So "if you are invited to an event and you check the menu in advance, [and] you find that the establishment is outside of your budget," your answer "should be no."

The kindest way to decline is by telling the organizer or guest of honor privately, without going into details as to why you can't join, Swann says.

From there, it's good practice to suggest another activity or outing within your budget that you can do together. It can be something as simple as a coffee date or spa night at home, Swann says, as long as your friend feels celebrated.

You might feel uncomfortable declining an invitation in the moment, but sticking to your budget is worth it. "Even with engaging in entertaining activity, we just cannot put ourselves into debt attempting to participate, just because we don't want to miss out," she adds, "because the after-effect of that can be long-lasting."

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