Released exclusively through Digital Spy, the posters feature Rafe Spall and Rose Byrne as mismatched newlyweds Josh and Nat.
Anna Faris co-stars as an ex-lover and old friend of Spall, while Simon Baker plays an ambitious American co-worker who takes a shine to Byrne.
Stephen Merchant, who appeared in a clip released yesterday, plays Spall's tactless and socially tone-deaf best friend.
I Give It A Year marks the directing debut of Brüno screenwriter Dan Mazer.
The film will be released on February 8 in the UK.
Watch the trailer for I Give It A Year below: