Burnham, who is widely expected to become prime minister later this year, is proposing a 50% increase in the threshold for 100% small business rates relief in England.
Forecasts by global tax firm Ryan suggest the policy could lift more than 140,000 additional small premises out of paying business rates altogether and reduce business rates liabilities by approximately £880m per year. The proposal would increase the threshold for 100% Small Business Rates Relief from a rateable value of £12,000 to £18,000, while extending the upper threshold for taper relief from £15,000 to £21,000.
Burnham has pledged to cover the costs through higher property taxes for large warehouses, particularly those run by online retail giants.
“Supporting small businesses is a great policy objective. The concern is how that is funded if things have to be revenue neutral,” says Alex Probyn, practice leader for Europe and Asia-Pacific property tax at Ryan.
“Larger commercial properties are already contributing more through the existing business rates surtax to fund lower liabilities for retail, hospitality and leisure. The obvious question is whether they are now going to be asked to contribute even more.”
Throughout his Makerfield election campaign, Burnham argued that ‘online giants’ should contribute more through higher taxation of large warehouses to support smaller businesses and Britain’s high streets.
Business rates reforms introduced in April 2026 included a 2.8p business rates surtax on properties with rateable values above £500,000 in England. The legislation already provides the Government with the ability to increase that surtax to as much as 10p, without introducing an entirely new tax.
“The attraction of increasing the existing surtax is obvious,” adds Probyn.
“It provides an established mechanism for funding additional reliefs elsewhere in the system. The risk is that higher property taxes increase the cost of occupying and investing in many of the sectors that underpin investment, jobs and economic growth.
“The primary issue remains that property taxes are now too high.”