The truancy problem is deepening among younger pupils despite a 10-year multi-million pound blitz on school absence including text alerts to parents.
And the trend is being partly fuelled by parents who defy head teachers and take children on unauthorised term-time family breaks in search of cheap holiday deals, official statistics showed.
Possibly test-oriented lessons could also be putting off the children, it is believed.
Ten per cent more primary pupils than last year are classed as 'persistent' absentees because they miss more than 20 per cent of school, it emerged.
And on any given day, more than 18,000 primary pupils are illicitly away from school following a shock eight per cent rise in the overall truancy rate.
Ministers hailed a reduction in truancy at secondary level, but they came under criticism for allowing more than 11million school days to be lost to the problem last year and its increasing prevalence in primaries.
The figures showed that the primary school truancy rate - the percentage of school registration sessions missed by pupils - was 0.56 per cent during the first two terms of the last academic year.
This is up from 0.52 per cent during the same period in 2006/07 and means an average of 18,275 pupils a day are truanting.
In 2005/06, under a less 'stringent' data collection method, it was 0.46 per cent.
This was similar to the figure for 1996/97, when it was 0.48 per cent.
The figures, published by the Department for Children, Schools and Families, also showed that a hard core of 81,530 primary pupils missed the equivalent of one day of lessons every week either through truancy or illness - up from 73,940 last year.
Officials have dubbed them 'persistent absentees' because they miss more than 20 per cent of registration sessions and made them a target of Government anti-truancy policies.
At secondary level, there are 191,240 persistent absentees despite a drop of 14,800 on last year.
The Tories said classroom indiscipline was the root of the problem.
Shadow Schools Minister Nick Gibb said: 'These figures are a stubborn reminder that the Government's multi-million pound strategy to tackle truancy has not succeeded. The truancy problem is now spreading to primary schools.
'Most alarming of all is the significant increase in the number of persistent absentees in primary schools which has risen by over ten per cent since last year.
'Bad behaviour in the classroom lies at the root of the truancy problem.'
But Mick Brookes, general secretary of the National Association of Head Teachers, said: 'We know that for some children, because they are not going to get their 'level four' at the end of the primary phase, that does have a turn-off effect and we can't afford that.
'If we turn children off education by the time they leave the primary sector, what hope is there for our colleagues at secondary level?'
David Laws, of the Lib Dems, said: 'The level of truancy is this country is deeply worrying. It is unacceptable that the equivalent of over 11 million school days are being lost each year.
'Today's figures make a mockery of New Labour's initial promises to make tackling truancy a priority.'
The truancy rate for primary and secondary schools combined was 0.97 - the same as last year.
The overall absence rate - encompassing both truancy and authorised absences due to illnesses and approved holidays - dropped slightly from 6.44 per cent of registration sessions to 6.26 per cent, Daily Mail reports.
But Children's Minister Baroness Morgan said: 'The vast majority of children have no unauthorised absence at all.
'The fact is that weak excuses no longer wash with schools - overall absence is going down because schools are taking on the persistent absentees.'