Terran R is a heavy-lift two-stage, partially reusable launch vehicle under development by Relativity Space.

[5] This planned version would be capable of putting 20,000 kg (44,000 lb) into low-Earth orbit (LEO) in recoverable configuration.

[6] On 12 April 2023, after the first flight of the Terran 1, Relativity Space CEO Tim Ellis announced that the rocket was no longer going to be further developed and focus would move to Terran R.[6] The new version of the rocket will have a maximum payload capacity of 23,500 kg (51,800 lb) to low earth orbit (LEO) with a fully reusable first stage, and 33,500 kg (73,900 lb) to LEO if fully expended.

[7] The first stage will use 13 Aeon R engines, producing an estimated thrust of 14.9 MN (3,350,000 lbs) in total.

[7] In July 2022, Relativity announced a partnership with Impulse Space to send a payload to Mars on the first Terran R flight,[9] which is expected to occur in 2026.