Later services to the Crown
On the accession of Queen Mary I in 1553, Gresham fell out of favour at Court for a short time with Alderman William Dauntsey displacing him. But Dauntsey's financial operations proved unsuccessful and Gresham was soon reinstated; and as he professed his zealous desire to serve the Queen, and manifested great adroitness both in negotiating loans and in smuggling money, arms and foreign goods, not only were his services retained throughout her reign (1553–1558), but besides his salary of twenty shillings per diem he received grants of church lands to the yearly value of £200 (equivalent to £72,866 in 2025).
Under Queen Elizabeth I's reign (1558–1603), besides continuing in his post as financial agent of the Crown, Gresham acted as Ambassador Plenipotentiary to the Court of Duchess Margaret of Parma, Governor of the Netherlands, and was appointed a Knight Bachelor in 1559 prior to his departure. The unsettled times preceding the Dutch revolt compelled him to leave Antwerp on 10 March 1567; but, though he spent the remainder of his life in London, he continued his business as merchant and government financial agent in much the same way as he had always done.
Gresham also acted, for Queen Elizabeth, as gaoler to Lady Mary Grey (sister of Lady Jane Grey), who, as a punishment for marrying Thomas Keyes the sergeant-porter, was imprisoned both in his Bishopsgate house as well as his other home, Osterley Park, from June 1569 to the end of 1572.