The 2018–2024 Odyssey uses the same key setup, so everything on this page applies to those years too. The full picture is on the Honda Odyssey key guide.

2021 Honda Odyssey: key facts

Key type: Smart / proximity key
Push-to-start: Yes
Transponder chip: G (ID47, Hitag 3)
Programming: OBD
All keys lost: We can originate new keys on site

Post-facelift fobs (KR5T4X, OEM 72147-THR-xx) still catalog as ID47/Hitag 3 — the Odyssey has not moved to the 4A platform. US vendor fitments for the KR5T4X fob agree with the catalog, but the chip listing itself is thinly sourced, so we confirm fob part number and tool coverage before an all-keys-lost quote.

Same key system as the 2018–2024 Odyssey

Honda kept the Odyssey's key system unchanged across 2018–2024, so everything about replacing a 2021 key — blanks, programming, and what happens if every key is lost — matches the rest of that run. The full year-by-year breakdown lives in our Honda Odyssey key guide.

What drives the price is the key type, whether you still have a working key, and where the car is parked. There's more on Honda programming in general on our Honda key page.

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Reviewed by David, Owner & Lead Technician, Wilshire Lock & Key — in the locksmith trade since 1987.

Last updated 2026-10-11.

2021 Honda Odyssey key replacement

2021 Honda Odyssey: key facts

Same key system as the 2018–2024 Odyssey

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