The Army sent a message to the Royal Navy ahead of their Twickenham showdown next month, while the RAF sealed the Inter Services title in Gloucester as both men's and women's sides faced off.
The Army men's 49-3 win means next week's match with the Navy will be an Inter Services title decider.
The Air Force defeat ends a miserable tournament for the current champions as they were comfortably beaten by both of their rivals.
In the 11:30am kick-off, the RAF women's side made history, being crowned Inter Services champions for the first time in over 20 years.
A 23-14 victory sealed the title win, sparking emotional scenes at full-time.
It was the first Army women's defeat in two decades.