Union Milnerton was established in 1973 with the amalgamation of Union and Milnerton Rugby Football clubs respectfully. It was this amalgamation that ensured the continuity of Union Rugby Club and at the same time afforded Milnerton Rugby Club the opportunity to play in the Grand Challenge League as it was known in those years.
The club has gone through many ups and downs over the years, from winning the club champs and playing in the Super A League to being relegated down to Division 1, In recent years the club has made a dramatic turnaround and in 2008 won the Division 1 league to be promoted to the Premier B league.
In 2013 Union-Milnerton had a phenomenal season by winning the Premier B League and were duly promoted to the Super B League.
After another great season in 2016 the club won the Super B League and was promoted to Super A League.
The club has consistantly ended up in the top 8 since 2017 and our best achievement has been ending 3rd in 2024 season.