Mr Stansfeld said he plans to apply for a “special funding” but he admitted police can only claim cash if the bill comes to over one per cent of the Thames Valley’s force annual budget.
He believes it will take “a long time” to establish the exact cost of Meghan and Harry’s wedding, but suggested it was “between £2m and £4m”.
The Duke and Duchess of Sussex were married in St George’s Chapel, Windsor Castle, on May 19, followed by a carriage procession through Windsor town and a reception in St George’s Hall.
Months of hard work went into planning the Royal Wedding, which saw more than 100,000 people head to Windsor to take part in the celebrations.
According to the Thames Valley force, Royal and Meghan’s wedding was the biggest operation ever conducted.
Mr Stansfeld said having to “carry” a bill of up to £4m was “not entirely satisfactory”.
The Police and Crime Commissioner (PCC) said the cost was currently “well below” the £4m required to make a claim.
However, he said the costs of “other major national events” coming up this year could be merged to get funding from the “special grant”.