Safety 1st onBoard 35 — expiration
Infant car seat.
Safety 1st ties the onBoard 35 to a 8-year useful life — the seats covered by the onBoard 35, onBoard 35 Air, onBoard 35 Air +, onBoard Air 360 infant-seat instruction manual, item 4358-8078 rev. 8.26.20, under its "Expiration" headin.
Do not use this car seat more than 8 years after the date of manufacture.
Safety 1st's own wording — source, checked 2026-08-27.
Read your label against the formula
Find the date of manufacture on the seat's label, then add 8 years — the same month. As Safety 1st applies it:
| Manufactured in | Reaches its stated life in |
|---|---|
| 2019 | 2027 (same month as your label) |
| 2020 | 2028 (same month as your label) |
| 2021 | 2029 (same month as your label) |
| 2022 | 2030 (same month as your label) |
| 2023 | 2031 (same month as your label) |
| 2024 | 2032 (same month as your label) |
| 2025 | 2033 (same month as your label) |
| 2026 | 2034 (same month as your label) |
Where the date is on this seat
Safety 1st's expiration page puts the date-of-manufacture sticker on the back of the seat, and describes that as true of "many" — not all — of their seats. Both manuals read this round place it on the side instead: "On the side of the car seat there is a date of manufacture label as shown." The same manuals send you to that side label for the model number, manufacture date and line code when registering. The spot is model-dependent, so follow the manual for your own seat.
Safety 1st's general guidance — source, checked 2026-08-27.
- Underside of the carrier shell
- Back of the seat shell
- On the separate base, top or side
Recalls
Run the label's model number and date of manufacture through NHTSA's recall lookup — it is the authoritative record for any seat, this one included.
The label on your seat is authoritative; this page is a reference.