He took part in the Capture of Belle Île in 1761. He was 2nd-in-charge at the capture of Havana during the 1762 British expedition against Cuba for which he received a significant amount of prize money nearly £25,000. Elliot was able to buy Bayley Park in East Sussex which he altered and enlarged over the decade. He was promoted Lieutenant-General in 1765. On 6 March 1775 he was made a Privy Counsellor and temporarily appointed commander of Forces in Ireland.