This is general information about federal consumer-reporting law, not advice about your specific circumstances. Statutes and regulations change; for guidance on your own situation, consult a licensed attorney.
A 611 letter and a 605B letter are not two brands of the same product. One is an accuracy dispute on a 30-day clock with no entry requirements; the other is an identity-theft block on a 4-business-day clock with four mandatory enclosures. Sending the wrong one costs weeks.
What is a 611 letter?
A 611 letter is a dispute sent under FCRA § 611, codified at 15 U.S.C. § 1681i. Once you notify a bureau that an item in your file is inaccurate, it must "free of charge, conduct a reasonable reinvestigation" and then "record the current status of the disputed information, or delete the item from the file" — all "before the end of the 30-day period" beginning when it receives your notice (§ 1681i(a)(1)(A)).
What makes § 611 the default tool is what it doesn't ask of you: the duty is triggered when accuracy "is disputed by the consumer and the consumer notifies the agency directly, or indirectly through a reseller." No police report, no affidavit, no notarization. That is the letter itself — our credit report dispute letter is built on this section.
One correction to a claim you will see everywhere: the 30 days becomes 45 only under § 1681i(a)(1)(B), where the bureau receives relevant information from you during that 30-day period. It has nothing to do with ordering a free annual report, and § 1681i(a)(1)(C) removes the extension once the item is found inaccurate or unverifiable.
What is a 605B letter?
A 605B letter is an identity-theft block request under 15 U.S.C. § 1681c-2, which the FTC publishes under the heading FCRA § 605B. The bureau must block the identified information "not later than 4 business days after the date of receipt" — roughly one-seventh of the § 611 clock.
The speed is bought with paperwork. Section 1681c-2(a) requires four enclosures: proof of your identity, a copy of an identity theft report, your identification of the information, and a statement that it does not relate to any transaction by you. An "identity theft report" is defined at 15 U.S.C. § 1681a(q)(4) as an official, valid report filed with a Federal, State, or local law enforcement agency and subject to criminal penalties for false filing; the CFPB says it "can be done through IdentityTheft.gov". Under 12 C.F.R. § 1022.3 it must allege identity theft "with as much specificity as the consumer can provide," and a bureau may still request more documentation — but only within fifteen days of receipt. Our identity theft block letter assembles all four.
Which letter do I actually need?
Send the 611 if the account is yours but something on it is wrong; send the 605B if the account isn't yours at all. That one question — is the account yours? — decides it:
- Yours, but something about it is wrong — the balance, payment status, date of first delinquency, a paid collection still showing owed. That is accuracy. Send the 611.
- Not yours, because someone opened it in your name. Send the 605B — and send a copy of the identity theft report to the furnisher too, because 15 U.S.C. § 1681s-2(a)(6) holds two different duties with two different triggers. Subsection (a)(6)(A) is triggered by the bureau: on the § 1681c-2 notification, the furnisher must have "reasonable procedures to respond" so as "to prevent that person from refurnishing such blocked information." Subsection (a)(6)(B) is triggered by you: it applies where "a consumer submits an identity theft report to a person who furnishes information to a consumer reporting agency at the address specified by that person for receiving such reports," and then bars that furnisher from furnishing "such information that purports to relate to the consumer" to any bureau, unless it later knows or is told the information is correct. The block alone gets you (A). Mailing the furnisher gets you (B).
- Accurate but old — neither letter applies. Under § 1681c(a) most adverse items drop off after seven years and bankruptcies after ten. For a delinquent account placed for collection or charged to profit and loss, the clock is set by a different subsection — § 1681c(c)(1), "Running of reporting period," not § 1681c(a) — which starts those seven years at "the expiration of the 180-day period beginning on the date of the commencement of the delinquency" that immediately preceded the collection activity. Re-aging that date is itself a 611 dispute.
Both letters live in the same place: the consumer letters category carries the 611 dispute and the 605B block side by side.
Can the bureau ignore or refuse my letter?
Not silently — and the two sections have different exits. Under § 1681i(a)(3), a bureau may terminate a reinvestigation it reasonably determines is "frivolous or irrelevant, including by reason of a failure by a consumer to provide sufficient information to investigate" — but it must tell you within 5 business days, with its reasons and a list of what it needs. A § 605B block has no frivolousness exit at all: under § 1681c-2(c) it can be declined only for a block made or requested in error, "a material misrepresentation of fact," or your having obtained goods, services, or money from the transaction.
Do I have to send it to the bank too?
The CFPB says to dispute in two places — the credit reporting company and the furnisher — and that "furnishers generally must investigate and respond to your dispute within 30 days". The hook is 15 U.S.C. § 1681s-2(b): on notice from the bureau, the furnisher must investigate, report back, and modify, delete, or permanently block inaccurate information — "before the expiration of the period under section 1681i(a)(1)." The point most guides skip: § 1681s-2(c) provides that §§ 1681n and 1681o "do not apply to any violation of subsection (a)," so the enforceable claim runs through that bureau-routed path. Writing only to the bank forfeits it.
What about a hard inquiry or a mixed file?
Neither is squarely a 611 problem. Your file disclosure must identify everyone who obtained your report — 2 years back for employment purposes, 1 year for any other purpose (15 U.S.C. § 1681g(a)(3)(A)) — and an unauthorized pull violates § 1681b(f), not § 1681i. In a July 2022 advisory opinion the CFPB stated that permissible purposes are consumer-specific — an advisory opinion is the agency's interpretation, not a court holding, so cite it as persuasive weight rather than settled law.
A mixed file runs on § 1681e(b) and its duty to "follow reasonable procedures to assure maximum possible accuracy." In a November 2021 advisory opinion the CFPB stated that matching on first and last names alone is not reasonable procedure under § 607(b). Cite the procedure failure, not a bare "not mine."
What happens if they blow the deadline?
Willful noncompliance carries statutory damages of "not less than $100 and not more than $1,000" plus punitive damages, costs, and attorney's fees (15 U.S.C. § 1681n(a)); negligent noncompliance carries actual damages plus costs and fees (§ 1681o), and suit must be filed by the earlier of 2 years after you discover the violation or 5 years after the violation occurs (§ 1681p) — the two are a ceiling, not a choice, so late discovery of an old violation does not buy you time. But a missed clock is evidence of noncompliance, not automatic deletion — § 1681i(a)(5)(A) conditions deletion on the results of the reinvestigation, not the calendar.
Send the right letter, dated and specific
Pull your report first. Every nationwide bureau — and, separately, every nationwide specialty bureau — must make your file disclosure "once during any 12-month period... without charge" (15 U.S.C. § 1681j(a)(1)(A) and § 1681j(a)(1)(C)); the specialty file is where a tenant-screening or check-writing entry hides. Then answer the one question — yours and wrong, or not yours — and send the letter that answers it, by certified mail, with the date and the account number on the page. Both are free in the letter template library.
Related: if the underlying problem isn't a credit report at all, our other free tools cover wills, SSDI appeals and letter drafting.
Frequently asked questions
What is a 611 letter? An accuracy dispute under 15 U.S.C. § 1681i. Free reinvestigation, 30 days, nothing to enclose.
What is the difference between a 611 and a 605B letter? The trigger. 611 needs only your say-so; 605B needs four enclosures and buys 4 business days instead of 30.
How long does a 611 dispute take? 30 days from receipt (§ 1681i(a)(1)(A)) — 45 only if you add relevant information inside that window.
Which letter if someone opened the account in my name? 605B. Then mail the identity theft report to the furnisher at its own specified address: that, not the bureau's block, triggers § 1681s-2(a)(6)(B).
Can the bureau refuse my dispute? A 611 can be terminated as "frivolous or irrelevant" with notice in 5 business days (§ 1681i(a)(3)). A 605B has no frivolousness exit — only the three grounds in § 1681c-2(c).
Do I dispute with the bank too? Yes, but route it through the bureau: the CFPB says both places, and only the bureau-triggered § 1681s-2(b) duty is privately enforceable.