Television:
* EastEnders (1985-2010, 2014-2016) as Arthur Fowler - Treacher's most famous role, he played the patriarch of the Fowler family for over two decades, becoming a beloved character on the soap opera.
* The Sweeney (1975-1978) - Appeared in two episodes as different characters.
* The Professionals (1977-1983) - Appeared in one episode as a character named Charlie.
* Juliet Bravo (1980-1985) - Appeared in multiple episodes as a character called Derek.
* Bergerac (1981-1991) - Appeared in one episode as a character named Frank.
* Midsomer Murders (1997-2019) - Appeared in one episode as a character called Charles.
* Heartbeat (1992-2010) - Appeared in three episodes as a character called Bill.
* Casualty (1986-present) - Appeared in several episodes as a character called Tom.
* The Bill (1984-2010) - Appeared in one episode as a character called Mr. Harris.
* Coronation Street (1960-present) - Appeared in a few episodes as a character called Eddie.
* Holby City (1999-2022) - Appeared in a few episodes as a character called George.
* Doctors (2000-present) - Appeared in a few episodes as a character called Bert.
Film:
* The Elephant Man (1980) - Played the character of the Hospital Porter.
* The French Lieutenant's Woman (1981) - Played the character of Charles Smithson.
* The Missionary (1982) - Played the character of Mr. Burgess.
* A Handful of Dust (1988) - Played the character of the Gardener.
* The Importance of Being Earnest (2002) - Played the character of the Butler.
* The Queen (2006) - Played the character of the Lord Chamberlain.
* The Other Boleyn Girl (2008) - Played the character of Thomas Howard.
This is not an exhaustive list, but it highlights some of Bill Treacher's most prominent roles across his career. He has also appeared in numerous stage productions and radio dramas.