In which year were both men and women granted the right to vote at 21?

Universal suffrage, meaning the right for all adult citizens to vote, wasn't achieved in one single step in the UK. It was a gradual process. The Representation of the People Act in 1918 was a major milestone, granting the vote to men over 21 and some women over 30 who met certain property qualifications. This was largely due to the contribution of women to the war effort during World War I. However, it wasn't full equality. Many people still couldn't vote. The final step came with the Representation of the People Act of 1928. This act lowered the voting age for women to 21, bringing it in line with men. So, 1928 is the key year because it marks the point when all adults, regardless of gender, had the right to vote at 21. The other dates are tempting because they represent earlier stages in the journey towards universal suffrage, but they don't represent the *complete* picture of equal voting rights.