It may be another few months before millions of students and families know how much they’ll have to pay for college this fall.

The troubled rollout of the new Free Application for Federal Student Aid, or FAFSA, form — and the revision of the formula for determining who gets federal financial aid — got worse on Tuesday when the Department of Education announced that it would not transmit data to schools until early March. The figures were supposed to start arriving the next day.

Many schools rely on the FAFSA to help them determine how much of their institutional money to give out in the form of grants that students will not have to repay. So until they have the information, any attempt to offer a price quote to current or recently admitted students may be just a rough estimate.

This delay is a particular problem for low-income students, for whom a few thousand dollars of difference can determine whether they start school at all or finish a program that they’ve already begun.

One reason for the delay is that the Education Department was late in updating some of its calculations for inflation. Completing that work means that 1.3 million people will get larger Pell Grants — the money the federal government makes available to lower-income students — than they would have otherwise.

The delay, however, disrupts the work of harried financial aid officers at schools, who are trying to digest the biggest changes to the system in decades without shutting it down during the reboot.