More than 100 schools have been allowed to run this month's tests later than the rest of the country, so their pupils will not miss expensive pre-booked trips.
Some schools faced losses of up to pound;1,000 last summer when the Government changed the dates of the tests to allow pupils more time to revise. Schools had paid deposits for expensive trips which clashed with the rescheduled tests.
The schools demanded compensation for lost deposits on any cancelled trips but the quango which runs the tests - the Qualifications and Curriculum Authority - instead ruled that the trips could go ahead and the tests be taken at a later date.
A QCA spokesman said: "We have treated each of these cases on an individual basis. There is not going to be one allotted slot for these schools to all sit the tests at once. These schools will run the tests at a later date which suits their circumstances."
This month's key stage 2 tests, taken by 600,000 1-year-olds will start on May 15 although they were originally timetabled to begin on May 8. Tests for 14-year-olds will be taken next week, not this.
The dates were changed after Education Secretary David Blunkett became concerned that this year's late Easter holiday could depress results. Headteachers had complained when they discovered that some schools would have just four days back after Easter before the primary tests. But schools which had planned to take pupils on a trip immediately after the tests were caught out.
A total of 124 schools applied to take the tests later because of a pre-arranged trip. But only schools that could prove their trip was booked before July 20 - the day the dates were changed - were permitted the change. The QCA approved 104 applications - 96 from primaries and eight from secondaries.
Six schools have received a total of pound;4,058 in compensation from the DFEE for lost deposits on cancelled trips. A spokesman said it was not too late for other schools to claim. Schools should contact their local authority or the DFEE on 020 7925 5000.