How to Wear a Number for a Triathlon

Sometimes the numbers are commonly drawn on.
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You are required to display your race number at all times during a triathlon. Failing to properly display your race number can cost you a variable time penalty. This penalty can add two to 18 minutes to your time, depending on the length of your race and the number of offenses. Penalty times are cumulative. Shorter races have smaller time penalties. The third offense results in disqualification. The race number violation is one of the most common triathlon penalties assessed. Fortunately, it's fairly simple to avoid this penalty.

Step 1

Mark your body with a permanent marker prior to your race. Most races have volunteers who will do this for you. The race you enter may specify where these numbers must be placed, so either have a volunteer mark you or check guidelines before having a friend mark you or marking yourself. Most races require your upper calf and upper arm to be marked. These numbers will identify you as you come out of the swim and transition to your bike.

Step 2

Attach your bike number to your bike frame. Remove the paper from the adhesive strips on the back of your bike number. Drape the number over your top tube so the printed number faces outward. Match the bottom edges so they are even. Press the two sides together to fasten the number securely. Remove the adhesive from the bike-helmet sticker that has your race number on it and secure it to the front of your helmet. These items identify you during the cycling leg of your race. When a bike number is supplied, your run number does not have to be worn during the bike leg, according to USA Triathlon.

Step 3

Attach your bib number to a race belt by slipping the race belt clips through the holes in the top of your bib. Clip your race belt around your waist during your bike-to-run transition so that the number is displayed to your front. Race belts are not supplied, but safety pins usually are. If you choose not to invest in one, use safety pins to attach your race number to the front of the shirt, jacket or tri suit you will wear during the run. Attach the number prior to the race, not during your bike-to-run transition.

Things You'll Need

  • Permanent marker

  • Race belt

  • Safety pins


If you attach your number to a jacket, you will not be able to remove the jacket during the run, because you also will remove your number. Using a race belt allows for more flexibility during cold-weather races, because you will be able to remove outer layers and still display your number.


Double-check that all fastenings are secure prior to starting your race.

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