How to look after a vintage Seiko: water, magnets, servicing

Updated 12 October 2026 · Cro Watches, Vilnius

A vintage Seiko is built to be worn, and with a little care it will keep going for decades more. These are the few things that matter.

Water: treat it as not water resistant

Most Seiko 5s left the factory water resistant to 30 or 50 metres, and divers to 150 metres. After 30 to 50 years, the rubber gaskets that keep water out have dried and shrunk. Unless the watch has been pressure-tested recently:

• Rain and washing your hands are fine.
• Take it off for showers, swimming and the sauna.
• Never pull out the crown when the watch is wet.

If you want to swim with it, a watchmaker can replace the gaskets and pressure-test the case, usually as part of a service.

Mist under the crystal? Take the watch to a watchmaker straight away. Moisture inside rusts a movement within days.

Magnets: the most common cause of a fast watch

If a watch that used to run well suddenly gains minutes a day, it has probably been magnetised by a phone, laptop, magnetic clasp or speaker. A watchmaker can demagnetise it in a minute, often free or for a few euros. To avoid it, don't leave the watch on top of a laptop or next to a speaker or a magnetic bag clasp.

How often to service

A service means the movement is taken apart, cleaned, oiled and adjusted. A good rule:

• Every 5–7 years for a watch you wear often, or
• when it tells you: it gains or loses more than a minute a day, stops after a few hours on the wrist, or the day and date stick.

For a Seiko 5 at an independent watchmaker in the EU, a basic service usually costs €60–120. Check how your watch performs with our accuracy checker.

Cleaning the bracelet and case

1. Take the bracelet off if you can (a cheap spring-bar tool does it).
2. Soak the bracelet only in warm water with a drop of washing-up liquid, then brush it with a soft toothbrush. Dry it well.
3. Wipe the case with a slightly damp cloth. Don't put a vintage watch head in water.
4. Don't polish the case unless you want to. Polishing rounds off the sharp edges that collectors value.

Storing it

• Keep it dry, away from magnets and out of direct sun, which can fade dials.
• An automatic doesn't need to be kept running. Let it stop; when you want to wear it, give it a gentle swing (see winding a Seiko 5) and set it.