The Evenflo Symphony expires 8 years after its date of manufacture, according to Evenflo.
What the maker says:
the Symphony car seat line expires 8 years after the date of manufacture, because it is an all-in-one car seat with extended use from infant seat through belt-positioning booster.
Note: FAQ names the line, not each model. Symphony manual PDF listed on /pages/manuals (us_symphony_EN.pdf) but not parsed.
Source: www.evenflo.com, checked 2026-10-24.
Look up another model, or work out the date from a manufacture date