Shrewsbury driving instructor Rob Gwilliams said he had tried to book a test for a pupil on Tuesday, only to be told that the earliest possible date was September 15.
Learners in Telford are being told that they must wait for at least 10 weeks before they can get a test date.
Mr Gwilliams said: "It's ridiculous really. We're told it's the shortage of examiners, and examiners having to cover other areas, as well as demand from more people wanting driving tests.
"It's a problem for the pupils, we are trying to get them ready, and that means we are having to book it when they are half ready in the hope that they will be ready in time for the test. But it is better doing that than having them waiting three months with nothing to do.
"It also means I am having to try to fit the new pupils in while we are still waiting for the existing pupils to take their test."
Mr Gwilliams said there were more problems if a pupil failed a test, as it could then mean them having to wait several more weeks before they could take a retest.
Paul Morris, who has been running his driving school in Bratton, Telford, since 1982, said at the moment the typical waiting time for a test at the Hortonwood centre was about 10 weeks.
"It's pretty bad at the moment, I was talking to an examiner recently, and he said it was because of the blanket ban on overtime," said Mr Morris.
"Not that long ago there was a wait of just one week, but more typically it is about four or five weeks, so it is a big increase."
John Lepine of the Motor Schools Association of Great Britain, said it was a problem right across Britain, with waits of up to 18 weeks in the most exceptional cases.
"It's very difficult to get somebody ready for a driving test when they don't know when the test will be," he said.
Ukip transport spokesman Jill Seymour from Wellington, has called for an urgent review of staffing levels at Britain's driving test centres.
Mrs Seymour claimed the Driver and Vehicle Standards Agency (DVSA) was making things even worse by pressing ahead with plans to close yet more test centres.
"Delays such as this are particularly damaging to young people who often rely on a driving licence to secure a job."
DVSA head of operations Phil Lloyd said there was a continued increase in demand for driving tests, and that the agency was seeking to address the problem by recruiting more examiners.
"We acknowledge that waiting times are currently higher than we would like. Recruitment campaigns across Great Britain in 2015 resulted in 193 new examiners starting work at test centres between April 2015 and March 2016."