Road riders tend to be particular about the bike and relaxed about the bits around it. Stay in the second group and you’ll be fine.
Start with what wears out. Tyres, chain lube, bar tape, socks and gloves all get used up. A fresh set is always welcome, and it’s hard to buy a duplicate of something they’ve already worn out.
Then think about winter. If they keep riding through December and January, overshoes, arm warmers and a thermal layer make a real difference. Our winter clothing deals page has more.
Tech needs one check. If they already use a Garmin or Wahoo computer, a Varia radar pairs with both. If they’re riding with a phone on the bars, a GPS computer is the gift they’ll remember.
Tyres need a size. Road tyres are marked on the sidewall, for example 700x28c. Take a photo of the tyre when they’re not looking and match it exactly.
Leave the contact points alone. Saddles, pedals and shoes depend on their body and on the cleats they already use. If they’ve asked for a specific model, fine. Otherwise, pick something else.