MPs claim some passport applicants who paid for a fast track service only to face delays earlier in the year were exploited.
In early summer the number of outstanding requests for passports reached more than 500,000 and now MPs on the Home Affairs Select Committee claim the state profiteered from charging £30 for a fast track service.
To bring the situation under control earlier this year the Passport Office took on more staff and extended opening hours.
In mid-June the office announced there would be a free upgrade to the fast track service offered to people who could prove they were travelling within seven days.
By late July around 16,000 people had been ungraded for free.
MPs on the committee criticised the government for not including those who had suffered delays and had to pay the extra fee themselves.
However, it is not suggesting those who upgraded as early as May 1 get a refund for the fast track service.
The committee’s chairman, Labour MP Keith Vaz, said: “The state should not be exploiting its own citizens by making a profit on what is a basic right.
“A British passport, an essential document for travel by British citizens, had become the subject of emergency statements and crisis management.”
A report into the delays said a number of people had “ended up out-of-pocket” as a result.
The Passport Office said it was working to ensure the delays didn’t occur again in the future.