Don't commit this beauty-salon blunder.

Tipping a hair stylist is a no-brainer, unless they also hold the title of owner. Some of us may be tempted to skip the tip in order to trim our final bill, but the practice isn't without plenty of debate. To get to the bottom of this age-old question, we chatted with Tricia Williams, owner of Alexandria, Virginia-based Salon 46.

Williams, who doesn't carry the dual title of stylist and owner, says the answer to this question has changed through the years, but she's decidedly in the always-tip camp—and for good reason.

"In the past, many salon owners charged significantly higher prices than regular stylists," she said. "Now salon owners do charge slightly higher prices than regular stylists, but it's more in line with their skill level, which is generally master stylist." Additionally, stylists are paid a higher commission than they previously were and oftentimes receive added benefits and bonuses. For these reasons, Williams says you should always tip your stylist regardless of whether she is the owner or not.

As for how much, she says it's standard to tip 15 percent, but tipping 20 percent or more for a stellar service is always appreciated.

Because we're always on the hunt for more salon etiquette know-how, we tapped Williams for her top tips for clients:

1. Be on time! It shows you respect your stylist's time and ensures you receive the full service that you booked.

2. Book your appointment ahead of time. Many stylists are booked weeks and months ahead, so their schedule is packed. During the holiday season it can be especially tough to get the day or time you want, so it's best to plan ahead.

3. Don't come straight from the gym or run to the salon. No explanation necessary here.