Thousands of officers were deployed to cover the four-day trip in the largest mobilisation since the 2011 riots.
Sara Thornton, who chairs the National Police Chiefs’ Council, said it was a “significant operation” with the US President visiting four force areas and protests taking place in many others.
She said: “Nearly every force supported the operation with nearly 10,000 officers deployed from all over the country, performing over 26,000 shifts. The full cost of the operation is still being worked out but an early estimate is nearly £18 m.”
Ms Thornton said all forces reported “high demand” at the time of the visit in July, which coincided with increased demand and calls linked to the World Cup, hot weather and events and festivals.
The senior officer added: “These demands affected local policing to differing degrees across the country with the host forces most impacted.
“The majority of forces had to cancel officers’ rest days and extend the length of their shifts.”
Making his first visit to the UK as president, Mr Trump held talks with Prime Minister Theresa May and met the Queen before travelling to Scotland where he played golf at his family’s Turnberry resort.