Premier League clubs have been exaggerating their attendances by as much as 12,000 spectators, new figures have revealed.

A study by the BBC of all 20 top-flight sides during the 2017-18 season found huge discrepancies in the attendances released by the clubs and those recorded by local authorities and police.

West Ham topped a list of clubs who have released potentially misleading numbers, but they are not the only ones, with Manchester City, Chelsea and Tottenham all found to have overstated official attendances.

West Ham exaggerated their average attendance during 2017-18, suggest official figures

Manchester City were found to have added an average of 7,482 to their attendance figures

Tottenham were also found to have added thousands of fans to records of their home matches

AVERAGE ATTENDANCES COMPARED TO AUTHORITY FIGURES Club Club figure (% of capacity) FOI figure (% of capacity) Difference (% of capacity) West Ham 55,309 (97%) 42,779 (75%) 12,530 (22%) Man City 53, 274 (97%) 45,792 (83%) 7,482 (14%) Southampton 29,906 (97%) 25,660 (79%) 4,246 (13%) Tottenham 61,843 (69%) 58,103 (65%) 3,740 (4%) Chelsea 40,593 (98%) 37,088 (89%) 3,505 (8%) Watford 20,319 (98%) 17,171 (80%) 2,602 (15%) Man Utd 73,575 (98%) 73,575 (98%) 0 (0%)

Figures divulged by Newham council following a Freedom of Information request by the BBC revealed that, across the 12 matches they attended at the London Stadium last term, an average crowd of 42,779 was recorded.

That number falls some way short of the figure released by the Hammers, who announced an average of 55,309 spectators throughout the campaign.

In one game alone, against West Brom on January 2, 17,523 fans were added. The club announced the official attendance of 56,888, however figures from the council revealed only 39,365 people had turned up.

While West Ham endured a difficult season on the pitch, the empty seats at the home of the champions are perhaps a little more difficult to explain.

According to Greater Manchester Police, who also worked on figures from 12 matches, the average attendance at the Etihad was 7,482 lower than the number given out by Manchester City.

That included the figures from the match against Southampton in November, where their attendance of 53,407 was 15,277 lower than the actual number of bodies inside the ground — 38,130.

Elsewhere, Hampshire Police records show Southampton exaggerated their crowds by 4,246 on average, while Tottenham added an extra 3,740 on average to their Wembley attendances according to Brent Council's numbers.

Hammersmith and Fulham council records revealed Chelsea to be supplementing their support by 3,505, while Hertfordshire Police suggested Watford were adding 2,602.

At one match, Newham council says the crowd was 17,523 lower than West Ham had said

Chelsea are one of the top-flight clubs to exaggerate their attendances, according to the BBC

WHERE DOES THE DIFFERENCE COME FROM? Premier League clubs will, more often than not, release the number of tickets sold as an attendance, rather than the actual bodies through the turnstyles. By law, they are required to know the number of people inside the ground and plan appropriately for the size of crowd expected. However, they do not need to release any of that information, and they are not breaking any FA or Premier League rules by using 'tickets sold' numbers. Advertisement

Interestingly, there was no disparity between the figures released by Manchester United and those collected by Greater Manchester Police and Trafford council.

A lot of made last season of the empty seats at the Emirates Stadium in Arsene Wenger's last season in charge, with the Arsenal Supporters' Trust reckoning that the average attendance was around 46,000, as opposed to the figure of 57,054 released by the club.

However, the club have disputed this figure and FOI requests made by the BBC were unable to confirm the Trust's position.

The difference in numbers mostly come from the decision from clubs to release the numbers of tickets sold, including all season tickets and complimentary tickets, as opposed to the number of bodies through the turnstyles.

The Football Supporters' Federation believes this is masking a problem with the effect of the growing number of TV matches.

A spokesperson told the BBC: 'Quite often clubs or the authorities will refer to "occupancy rates" in their arguments.

'But they are often misleading according to the BBC's research and don't highlight how many fans stay away when matches are rescheduled for TV.

'If clubs know the actual number of fans through the turnstile, rather than the number of tickets sold or given away, then there's no reason they shouldn't publish that figure.'

Oddly, the study also found that Tottenham had understated attendances for some Wembley fixtures — including the Premier League's record attendance.

The north London derby at the national stadium actually saw 83,290 people attend, 68 more than originally stated.