What Is a GMT Watch?

A GMT watch tells the time in two places at once. Alongside the usual hour, minute and seconds hands it has a fourth hand that goes round the dial once every 24 hours instead of every 12, pointing at a 24 hour scale on the bezel or the dial. Set that hand to your home time and the main hands to wherever you are, and a glance tells you whether it is a reasonable hour to call home.

The idea dates from the 1950s, when long haul jet travel became routine and airline crews needed to keep track of the time at their base while flying across several zones. The name comes from Greenwich Mean Time, the reference time pilots navigated by. Since then the GMT has become one of the most popular sports watch formats, and its two colour bezel one of the most copied looks in watchmaking.

How does a GMT watch work?

The 24 hour hand is driven by the same movement as the other hands, through an extra gear that turns it at half the speed of the hour hand. Because it takes a full day to make one revolution, its position alone tells you whether it is morning, afternoon or night in the second zone. That is the advantage over simply reading a second set of twelve hours: there is no ambiguity about whether 7 means 7 in the morning or 7 in the evening.

The scale it points to is marked 2, 4, 6 and so on up to 24, usually on the bezel. On the classic travel watch, the bezel is split into two colours, one half for the daylight hours from 6 to 18 and the other for the night. That two colour split is functional, not decorative: it lets you read day or night in the other time zone without reading any numbers.

Price tracker · prices checked October 9, 2026

Price history: Imperial

What one watch has cost over time, listed and per watch while the store ran its offer.

How do you read and set one?

Exact steps depend on the movement, but the logic is always the same:

1. Set the main hands to local time, wherever you are.
2. Set the 24 hour hand to your second zone, usually home. If it is 3 in the afternoon at home, the hand points to 15 on the 24 hour scale.
3. Leave the bezel at zero (the triangle at the top) to read the 24 hour hand against it directly.
4. For a third zone, rotate the bezel by the hour difference. If the third city is three hours ahead of your second zone, turn the bezel so that 3 hours sits where 24 was, and read the same hand against it.

Many GMT watches also let you read UTC, the modern successor to Greenwich Mean Time, if you set the 24 hour hand to it. Pilots and radio operators often do exactly that.

Flyer or office GMT?

Mechanical GMT movements come in two designs, and enthusiasts care about the difference:

• "Flyer" or true GMT: the local hour hand jumps forward or back in one hour steps without stopping the watch. When you land, you change the local time in seconds and the home time stays put. This is the more expensive and more convenient design for travelers.
• "Caller" or office GMT: the 24 hour hand is the one that jumps on its own. It suits someone who stays home and keeps track of colleagues in another zone, and it is cheaper to build.

Quartz GMT watches usually set each hand separately through the crown, and the instruction sheet tells you which position does what.

GMT function or GMT look?

This is where buyers need to be careful. The two colour rotating bezel is so closely associated with GMT watches that it now appears on plenty of watches that have no 24 hour hand at all. Without the fourth hand, the 24 hour scale on the bezel cannot show a second time zone on its own; it becomes a styling feature.

The quickest test is to count the hands in the product photos. A GMT has four hands from the centre, one of them usually a different colour with an arrow tip, and that hand will point somewhere different from the hour hand. If you count three, you are looking at the look rather than the function.

A three hand watch with a rotating 12 hour bezel can still track a second zone in a simple way: turn the bezel by the hour difference and read the hour hand against it. It does not tell you day from night, but for a single trip it works.

What does a GMT cost?

At the top of the market, the best known two colour bezel steel travel watches start at about $11,500 at retail and sell well above that on the secondary market. Several Japanese and Swiss makers offer mechanical GMTs for under $1,500, and quartz GMTs are available for a few hundred dollars from established brands.

If what you want is the look, the red and blue bezel, the five link steel bracelet and the sports watch proportions, the Lucky Fours Imperial is far less money. It is a Quartz watch, and we treat it as a two colour bezel watch rather than a GMT: before buying, look at the photos for the colourway you want and count the hands, using the test above. The comparison with real quartz and mechanical GMTs is in our two colour bezel travel watch guide.

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For the bezel itself, and how a rotating scale differs from a dive timer, see what a dive bezel is. Every part of a watch case and dial, including the bezel inserts and hands mentioned here, is labelled in our watch anatomy guide.

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