FirstBank: email security grade A

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FirstBank, Nashville, Tennessee, is the 114th largest FDIC-insured US bank by total assets ($17bn). On 4 November 2026 the public email records of firstbankonline.com graded A: MX pass, SPF pass, DMARC p=reject, mail handled by Mimecast.

Grade A. Nothing in the records will stop mail. Read by DNS on 4 November 2026; the records are shown as published.

What was found on firstbankonline.com

Check	Result	What was published
MX	Pass	`10 us-smtp-inbound-1.mimecast.com`, `20 us-smtp-inbound-2.mimecast.com`. Mail handled by Mimecast
SPF	Pass	`v=spf1 redirect=2hbn3r6q._spf._d.mim.ec`. DNS lookups: 9 of 10 allowed; ends ~all
DMARC	Pass	`v=DMARC1; p=reject; rua=mailto:07596fd31ef8627@rep.dmarcanalyzer.com; ruf=mailto:07596fd31ef8627@for.dmarcanalyzer.com; fo=1;`. Policy p=reject; reports collected (rua= set)
DKIM	Pass, not graded	Key found on selectors s1, s2 (of 10 common selectors tried)

Where FirstBank ranks

FirstBank is the 114th largest FDIC-insured US bank by total assets, at $17bn as reported to the FDIC (certificate 8663; Nashville, Tennessee). Among the 999 graded banks, FirstBank ranks 88th by grade (ties broken by assets, larger first). In its asset band, $10bn to $100bn, it ranks 58th of 122; among the 31 graded banks in Tennessee, 3rd. 69.7% of its band and 54.8% of its state graded A.

What this means for the bank

The checker's own notes on each record:

MX, pass: 2 MX records. Replies have somewhere to land.
SPF, pass: One SPF record, ending in ~all (softfail): mail from a server that is not on the list is treated as suspect.
SPF, info: The record hands over to 2hbn3r6q._spf._d.mim.ec with redirect=, so its ending comes from that record.
SPF, info: DNS lookups: about 9 of the 10 allowed. One more sending service could push it over. This count is an estimate.
DMARC, pass: Policy p=reject: receivers are asked to refuse mail that fails.
DMARC, info: Reports go to 07596fd31ef8627@rep.dmarcanalyzer.com.
DKIM, pass: DKIM key found at s1._domainkey.firstbankonline.com, about 2048-bit RSA.
DKIM, pass: DKIM key found at s2._domainkey.firstbankonline.com, about 1024-bit RSA.

What this means if you sell to FirstBank

FirstBank routes inbound mail through Mimecast, a filtering gateway. Expect strict inbound filtering: a message from a sender whose SPF, DKIM or DMARC fails, or whose domain has little sending history, is unlikely to reach a person. Before you send, run your own domain through the email setup checker and publish a policy with the DMARC record generator. For how a bank buys, see the selling to banks playbook.

Check it live

The records above are from 4 November 2026. Run the same check on firstbankonline.com now for today's result. The FDIC's record of the bank is at BankFind, certificate 8663.

This page is one of 1,000 in the Bank Email Readiness Index Q4 2026, published 4 November 2026 and re-read every quarter; the next edition is due 2 February 2027. If you work at FirstBank and the records have changed, email moe@roimaxi.com and we will re-check and update this page.

ROI Maximizer is a trading name of M Ventures LTD, registered in England and Wales, company no. 15554493. Registered office: 4 Beau Street, Bath BA1 1QY, United Kingdom. moe@roimaxi.com