The additional places were offered on Tuesday under the random allocation system in accordance with the Department for Education School Admissions Code and the school's admissions policy.
Governors said the additional places would "create movement across schools in the hope that those still awaiting a place in a Jewish school will receive an offer.
"We know that the lengthy decision process may have caused some anxiety for those families awaiting a place but it has been important to undertake a thorough internal analysis to ensure the school can take an additional form.
"While doing so creates additional financial and operational challenges, we are pleased to have been able to alleviate some the pressure in the system."
They said JFS had worked closely with other Jewish secondaries and the Jewish Leadership Council's schools network, Pajes.
The Institute for Jewish Policy Research had warned that mainstream Jewish secondary schools could face their highest number of first-choice applications this year.
Rabbi David Meyer, executive director of Pajes, said, “It is a credit to the secondary schools that they continue to work together to ensure sufficient provision across the community. Thanks to this extra class offered by JFS we would anticipate that those who wish to attend a Jewish school will be able to do so.”