Dr. Matthew "Matt" Carter was a GP at the Rosamund Street Medical Centre, one of whose first patients was Natasha Blakeman in August 2010. She had discovered she was pregnant and aborted the baby when the unborn child’s father Nick Tilsley, not knowing she was pregnant, finished with her and then promptly changed his mind when he heard the true state of affairs. She went to see Dr Carter to see how quickly she could get pregnant again, but was told that it would take at least a month before she could.
Nick called at the centre to chat with his mother, Gail who worked as the receptionist at the time, and burst into the consulting room as the “proud father” when he heard that Natasha was in there. Dr Carter didn’t break his patient confidentiality and reveal that the baby was no more and assured Natasha that Gail had no access to her medical records. He also told Gail that he was unhappy she’d told Nick that Natasha was in his surgery and warned her that a repeat occurrence would lead to her sacking.
A few days later Nick was still ignorant of events and enthusiastically pushed Natasha into attending an early pregnancy class for parents at the centre. Dr Carter was surprised to see her there but still maintained her confidentiality and the class proceeded as normal. When Gail looked through Natasha's medical records and told Nick which led to them breaking up, Natasha filed a complaint against Gail and Dr Carter sacked her.
On the night of 6th December 2010, a tram crashed into the Street after an explosion at The Joinery bar. Matt opened up the medical centre and assisted in helping the injured. He also began supporting John and Fiz Stape after Fiz gave birth to a premature baby girl called Hope. When John had a mental breakdown a month later (unknown to people the cause was due to him accidentally killing Joy Fishwick) Matt admitted him to Weatherfield General for treatment.
Later in the year Matt began chatting up barmaid Tina McIntyre and they began to date, much to the dismay of Tommy Duckworth who was in love with her. Matt began taking her out for meals and parties although she felt slightly out of place with people higher up than her. During a date at Nick's Bistro in November 2011, Tina was alarmed to discover that an old university friend - Jenny - had actually dated Matt on and off for five years. Matt attempted to convince Tina to do better for herself rather than be a barmaid, so had suggested she should do some courses, but Tina refused as she had preferred her bar work and thought Matt was embarrassed by her occupation. They then separated, with Tina throwing a pint over Matt.
In March 2013 Matt took part in a Full Monty show at the Bistro with some of the other street's male residents when firemen who where originally going to take part in it had fallen ill. He was a bit sceptical about getting fully undressed as he had to work in the community, but the show was then interrupted half-way through when a fire occurred at the Rovers Return Inn.
He left the medical centre in July that year.
- Oliver Mellor was originally signed for four episodes in the role of Dr Carter as part of Natasha Blakeman's exit storyline, with a hinted possibility of a return for a longer stint. The character then continued to appear on a recurring basis.
- In June 2013, Mellor decided to quit the show when he felt that his character wasn't progressing. His final scenes aired in April that year without an on-screen exit. In July, the character's departure was mentioned by Deirdre Barlow when she stated that his new replacement wouldn't be a patch on him.