With so many of us glued to our phones and using wearable tech, perhaps the strangest trend of the 2020s is that watches—especially vintage luxury ones—have   made a comeback, especially among Millennials and Gen Zers.

The uptick in interest for watches that make fashion statements also means repair shops are back in demand. Fortunately, our surveys of watch repair customers found that many shops that do great work at fair prices.

Before plopping down your watch at a shop, ask about its guarantees. Most will guarantee overhauls (disassembling, cleaning, lubricating, regulating) and other major repairs for between six months and one year. Those usually apply only to movement-related repairs (stoppage, failure to run properly); replacing of a crystal, for example, probably won’t be under warranty.

Some shops send out repairs, but it’s better to find a place with an onsite watchmaker who can answer questions, determine whether repairs are feasible and worth the money, provide an accurate estimate, and do easy fixes on the spot.

You can look for shops with pros certified by the American Watchmakers-Clockmakers Institute, though many capable ones have never become certified.

When our undercover shoppers called shops and requested prices for three different jobs, we found big price differences: The highest prices were more than twice as high as the lowest ones. And some watch repair shops that charge low prices often also do great work: We found that lower-priced shops scored about the same as higher-priced businesses, on average, on our survey’s “doing work properly” question.

These care tips will help your watch last longer:

Be wary of water. “Water resistant” means the watch is protected from accidental wetting. Don’t wear it to shower or swim. If it gets wet, dry it as soon as possible. With watches specially designed for underwater use, comply with the conditions specified in the manufacturer’s instructions.

Even if your watch is “shock resistant,” as most are, don’t press your luck. Take it off before operating a jackhammer, rushing the quarterback, and similar activities.

Don’t try to repair your watch yourself. Leave it to a professional.

Replace a dead battery in your watch immediately. It might leak or corrode.

Replace a cracked crystal right away. Even a tiny crack can allow dust or moisture inside and interfere with the mechanism.

Have a mechanical (as opposed to battery-powered) watch serviced every couple of years, unless the manufacturer suggests a longer interval. Tiny particles of dust can get inside, increasing friction on moving parts. As a rule of thumb, the smaller the watch, the more it will be affected by dirt or lack of lubricant because the parts—including the mainspring—are smaller and more delicate. Women’s watches generally need more frequent overhauls than men’s models.

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