The Government expects to spend $6 million less than it had planned on immunisation this financial year.
The under-spending on immunisation is revealed in background papers issued with last week's Budget.
The documents say spending on immunisation is expected to be $6.28 million less than was budgeted for this year.
That amount has been re-prioritised for spending elsewhere, but it's not specified what on exactly.
The Ministry of Health says the under-spending was due to efficiency gains and better prices negotiated by it for vaccines.
A spokesperson for the minister says there was also a slower uptake than expected of the Gardasil cervical cancer vaccine by young women and teenage girls.
The papers also show a settlement for patients treated in psychiatric hospitals before 1992, cost the ministry up to $6 million this year.
