If you are over the age of 40, the health body says you should be getting it checked every five years.
As many as five million adults in the UK have undiagnosed high blood pressure, so will not know that they are at risk, according to the British Heart Foundation.
Blood pressure is defined as the force put on your blood vessels and organs as blood is pumped around your body by your heart.
Blood pressure is recorded with two numbers. The systolic pressure, higher number, is the force at which your heart pumps blood around your body.