Bowes made a career at the Royal Mint, as a master-worker and under-treasurer, and personally contributed to the debasement of English currency. He was a Sheriff of London for 1540 and the Lord Mayor of London for 1545. From 1547 to 1553, the reign of Edward VI of England, he represented the City of London in Parliament. He was one of the interrogators of Anne Askew, who was burnt at the stake for heresy in 1546. , built by Bowes in the 1540s During the 1520s and 1530 Bowes was one of three or four master-workers of the Royal Mint. The three master-workers and the Treasurer, William Blount, 4th Baron Mountjoy, were entitled to equal shares of the Mint's profit. The arrangement caused friction between the master-workers and their noble superior, who claimed to have been denied his fair share. Official allowances paid to the master-workers were considerably lower than in the preceding Yorkist period, and the managers "compensated" themselves with "seizing every opportunity to make the Mint pay". Earlier, king Henry VII enforced tight control over the Mints, but under Henry VIII the Crown "did little more than making the ends meet", and let the master-workers on their own. Investigations that led to reorganization of the Mint in 1544 showed that Bowes and Ralph Rowlett were responsible for systematical unauthorized debasement of silver supplied by the Crown. Thousands of pounds in "surplus" coinage remained unaccounted for, but Bowes survived the scrutiny. During the reform of the Royal Mint in the 1540s Bowes, now promoted to Under-treasurer, remained in charge of the Royal Mint in Tower. His long experience and influence of the Mint were partially offset by an appointment of the second under-treasurer, Stephen Vaughan. Vaughan, involved in financial affairs of the Crown in the Low Countries, did not have much time to spend at the Mint. Bowes, again, remained in command, now engaged in authorized full-scale debasement of English currency. According to Challis, in 1544–1551 the Tower I facility managed by Bowes produced silver coinage valued at £957,067 and gold coins valued at £767,362, or 43% out of total national output. Bowes was responsible for around one quarter of the debased testoon production, in which £385,000 worth of good silver currency were reworked into £547,000 of new currency. These poorly based testoons became known as "base testoons". In total, Bowes "generated" around a third of Crown's profits from the debasement of currency - £421,693. His production overheads, at 1/26 of net profits, were higher than those of his peer Thomas Knight, because Bowes bore the costs of management, engravers and potmakers for both facilities.
Family
Bowes married firstly, by 1526, Cecily Eliott. He married secondly, by 1538, Anne, the daughter of John Barrett of Belhus in Aveley, Essex. By his first two marriages he had eighteen children, including:
Thomas Bowes, eldest son, who married Cecily, the widow of Thomas Haynes.
Martin Bowes, who married firstly Frances Scrope, the granddaughter of Robert Amadas. According to the Diary of Henry Machyn, she was buried 29 December 1566. He married secondly, Frances Clopton, the daughter of Richard Clopton and his second wife, Margery Playters. After her first husband's death, Frances married secondly, as his third wife, Matthew Hutton, Archbishop of York.
In 1554 Bowes married thirdly, Elizabeth Harlow, the daughter of Thomas Harlow and widow of William Billingsley. and they had at least one son, perhaps named William,
