What a freeze does not stop is set out in the statute. 15 USC 1681c-1(i)(4) lists ten categories a freeze does not apply to, and a frozen file remains available to each of them: a person the consumer already has or had an account or contract with, its affiliates, agents and assignees, for the purpose of reviewing the account or collecting on it, with "reviewing the account" expressly defined to include "account maintenance, monitoring, credit line increases, and account upgrades and enhancements"; a collection agency acting under a court order, warrant or subpoena, and federal, state or local agencies, law enforcement and trial courts so acting; a child support agency; a federal or state agency investigating fraud or collecting delinquent taxes or unpaid court orders; prescreened credit and insurance offers; a file monitoring service you subscribed to; anyone providing you with your own report or score at your request; anyone underwriting insurance; anyone using the information for employment, tenant or background screening; and anyone verifying your identity for a purpose other than granting credit.
Read that list against what a freeze is usually taken to mean. It blocks new credit. It does not stop an existing card issuer reviewing your account, or a landlord screening you, or an insurer pricing a policy.
The deadlines are asymmetric, and the faster one is the lift. Under 1681c-1(i)(2)(A) a bureau must place a freeze free of charge within 1 business day of a request made by toll-free telephone or secure electronic means, or within 3 business days of a request by mail. Under (i)(3)(C) it must remove one free of charge within 1 hour of a telephone or secure electronic request, or 3 business days by mail. That one-hour figure is the answer to the standard objection that a freeze will get in the way when you actually want credit.
A freeze is permanent until you say otherwise. (i)(3)(A) allows a bureau to remove one only on the consumer's direct request or where it was placed due to a material misrepresentation of fact, and (i)(3)(B) requires written notice before a removal of the second kind. There is no expiry date, which is the clearest difference from a fraud alert.
Temporary removal is a statutory right, not a workaround. (i)(3)(E) provides that if a consumer asks for a temporary removal, the bureau must remove the freeze "for the period of time specified by the consumer". So applying for a mortgage does not require abandoning the freeze.
Three smaller mechanics that matter in practice. Within 5 business days of placing a freeze, the bureau must confirm it and tell you how to remove it and about your right to opt out of prescreened offers ((i)(2)(B)). If a third party asks for a frozen report in connection with a credit application and cannot get it, it "may treat the application as incomplete" ((i)(3)(D)), which is why a lender may simply stop rather than tell you what happened. And each bureau must maintain a webpage for freeze and alert requests that "shall not be the only mechanism" for making them ((i)(6)(A)), so telephone access has to remain.
A separate subsection covers children and protected adults. Under 15 USC 1681c-1(j), a representative may freeze the file of a protected consumer, defined as someone under the age of 16 at the time of the request or an incapacitated or protected person for whom a guardian or conservator has been appointed. If no file exists, the bureau creates a record for the purpose. Note this freeze is drawn more narrowly than the adult version: it blocks disclosure to a person requesting the report "for the purpose of opening a new account involving the extension of credit."