The money schools get from the Department of Education to provide free period products has been cut by more than 40%.
The department said that the fall was "due to a combination of budget reductions and the level of need being lower than expected in 2022-23".
The annual funding for education was cut in the recent budget from Northern Ireland Secretary Chris Heaton-Harris.
Some schemes aimed at disadvantaged pupils have been stopped to save money.
Funding for a three-year scheme to address "period dignity" in schools was approved by the Stormont Executive in 2021.
It was separate from - but related to - a law to provide free period products to everyone in Northern Ireland who needed them.
