If you’re used to filling your wallet with plastic, not paper, don’t forget to carry some cash the next time you hit the road. Here’s why…

It may come as no surprise that cash is still king in some developing countries.

After all, the corner noodle shop in Vietnam or roadside stand in India probably doesn’t take Visa.

But remember, a lot of mom-and-pop shops in the U.S. also still have cash-only policies.

Those smaller establishments can’t swallow the 3 percent fees levied by credit-card companies, so requiring cash keeps their prices lower.

And don’t forget about transportation. While yellow cabs in New York now accept credit cards, that’s not a luxury you have in most cities around the world.

Some countries require that you pay a cash-only airport tax when you arrive or depart.

That’s true in South American countries like Venezuela, Peru and Brazil, and in many parts of the Caribbean.

And in Middle Eastern countries like Egypt, tipping in cash isn’t limited to your waiter and bellman.

If someone holds the door open for you, they’ll probably hold out their hand for a few coins.

Get Tips on Tipping Around the World.

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