The British Heart Foundation is investing £1.5million in projects to reach people who are less likely to go to their GP surgery for a test.
The charity estimates that seven million people are living with undiagnosed high blood pressure.
Experts estimate the consequences of the condition costs the NHS £2billion every year, while social care and economic costs are likely to be much higher.
High blood pressure – often known as the “silent killer” – affects nearly a third of adults across the UK.
But it is undiagnosed and untreated in 40 per cent of cases.
Sufferers are up to three times more likely to have a stroke or develop heart disease.
The charity has awarded two rounds of funding for innovative projects which will explore the best ways of diagnosing high blood pressure, beyond GP surgeries.
It is supporting 15 projects across the country over two years.
Each project will need to reach and test the blood pressure of at least 5,000 people a year, who are not already diagnosed.
Jacob West, director of healthcare innovation, said: “We urgently need to find the millions of people across the UK living with undiagnosed high blood pressure.
“This means learning from countries like Canada, where knowing your blood pressure has become as common as knowing your weight or PIN code.”
Professor Jamie Waterall, of Public Health England, added: “High blood pressure is the leading cause of heart attacks and strokes, but it is largely preventable and easily treated. Improving access to checks will help more people.”