The police investigation into the disappearance of RAF serviceman Corrie McKeague has cost more than £2.1m to date.
The 23-year-old, who was based at RAF Honington, disappeared on a night out in Bury St Edmunds in September 2016.
Suffolk Police said the investigation has cost £1,325,000 plus salary costs of £826,000.
Police conducted two searches of a landfill site at Milton near Cambridge last year, with the first search lasting 20 weeks and the second, lasting seven weeks.
No trace of Mr McKeague was found in either searches, but police said they will explore other lines of enquiry into the airman's disappearance.
In December, officers said they were 'content' Corrie is not in the landfill areas which have now been searched.
The force said around 34,000 police officer hours had been spent on the investigation, not including police staff time or overtime hours.
Suffolk force said "careful consideration" was given to resourcing all major, long-running investigations.
It is thought Mr McKeague may have climbed into a waste bin and was taken away by a bin lorry, prompting the landfill search.
A review of the police investigation to date agreed that it was most likely that Mr McKeague ended up in the waste disposal process.
Police have said officers are "committed to continuing with the inquiry".
Corrie's mother Nicola Urquart is still urging people who may have any information to come forward.
She told the 'Find Corrie' Facebook page: "I am using this time to go over all the information I have to see if there is anything that maybe the police or I didn't feel relevant or important at the time but now may be.
"Just like the police I have gone back to the beginning and am testing every possible scenario I can think of and how we could prove it is or isn't possible.
"The answer is out there. Just like Corrie is out there somewhere."