If you do not receive written confirmation, it gets you off the hook on providing provisional credit as noted in 1005.11(c)(2)(i)(A), but it does not get you off the hook of conducting an investigation. Absence of written confirmation does not constitute evidence that no error occurred.
See
CFPB Reg E Investigation FAQ #4QUESTION 4:
Can a financial institution require a consumer to file a police report or other documentation as a condition of initiating an error resolution investigation?
ANSWER (UPDATED 6/4/2021):
No. A financial institution must begin its investigation promptly upon receipt of an oral or written notice of error and
may not delay initiating or completing an investigation pending receipt of information from the consumer. See Comments 11(b)(1)-2 and 11(c)-2. In the past, Bureau examiners found that one or more financial institutions failed to initiate and complete reasonable error resolution investigations pending the receipt of additional information required by the institution. These examples can be found in the Bureau’s Summer 2020 edition of Supervisory Highlights and Fall 2014 edition of Supervisory Highlights. The Bureau cited similar violations in 2019-BCFP-0001
And
FDIC June 2019 Supervisory HighlightsNot beginning the investigation promptly when notified of a potential error.
An institution’s investigation of an error claim must begin promptly upon the receipt of an oral notification, even if the institution requires the
consumer to provide written confirmation of the error under Section 1005.11(b)(2) in the Official Interpretations to Regulation E. After receiving an oral notification regarding an error, the institution may require confirmation of the error in writing from the consumer. If the institution requires written confirmation of an alleged account error, and the confirmation is not received within 10 business days, the institution need not provide provisional credit to the consumer while investigating the error. Nevertheless, as provided in the Official Interpretations to Regulation E, 12 C.F.R Part 1005, Supp. I, Section 1005.11(c)(2), a financial institution “must begin its investigation promptly upon receipt of an oral notice. It may not delay until it has received a written confirmation. ”
The FDIC found some financial institutions failed to investigate consumer error claims promptly upon receipt of oral notification in violation of Regulation E.