Domain reputation 101: DMARC, SPF, DKIM, and blocklists for GoHighLevel senders

Sender reputation is what mailbox providers actually use to decide whether your message lands in the inbox, the promotions tab, or the spam folder. It's calculated per sending domain (and per IP for shared infrastructure like GoHighLevel's), and it's built up — or destroyed — by every send you make.

The good news: the levers that move it are mostly mechanical. Get authentication right, keep your bounce and complaint rates low, stay off the major blocklists, and the providers will lean toward delivering. This guide walks through the four checks every GoHighLevel agency should run on every sending domain, and what to do when one of them fails.

The four-step domain reputation audit

1. 1

   Publish DMARC at p=quarantine or p=reject

   DMARC tells mailbox providers what to do with mail that fails SPF and DKIM alignment for your domain. p=none gathers reports without enforcement; p=quarantine sends failures to spam; p=reject drops them entirely. Aim for p=reject with rua= reports flowing to MailerMonk so you see every authentication failure.

2. 2

   Audit SPF for the 10-lookup limit

   SPF is capped at 10 DNS lookups per evaluation by RFC 7208. ESPs that chain include: directives (Mailgun, Sendgrid, GoHighLevel itself) eat through the limit fast. Use the SPF checker to count your lookups and flatten or trim includes if you're over.

3. 3

   Rotate DKIM keys and use 2048-bit signatures

   Many older setups still publish 1024-bit DKIM keys, which Google has been quietly pushing senders to upgrade. Rotate to 2048-bit keys at least once a year, and confirm the public key is published correctly with the DKIM checker.

4. 4

   Monitor your domain across the major blocklists

   Spamhaus DBL, SURBL, URIBL, and Barracuda are the lists that actually move the needle. A domain listing on any of these will degrade delivery within hours. MailerMonk checks all four daily and pings you the moment a listing appears, with the delisting URL pre-filled.

Why GoHighLevel-shared sending makes domain auth more important

By default, GoHighLevel sends from shared infrastructure, which means your IP reputation is mixed with every other sender on the same range. The one piece of reputation you fully control is your domain's. Strong DMARC + DKIM alignment lets mailbox providers attribute good behavior to your domain regardless of the IP it came from.

Practically, this means: never send from gmail.com or yahoo.com (DMARC will block you), always set up a custom sending domain with full SPF/DKIM/DMARC, and prefer a subdomain (e.g. send.yourbrand.com) for marketing so any reputation hits don't affect your transactional or human email.

Reading DMARC aggregate reports without losing your mind

DMARC aggregate (RUA) reports arrive as XML attachments from every major mailbox provider, daily. Reading them by hand is miserable — they're machine formats, not human ones. Tools like MailerMonk parse and aggregate them for you, surfacing the things that matter: who's spoofing your domain, which legitimate senders are failing alignment, and which sources you should add to SPF.

Set up rua= on your DMARC record to point at a parsing tool from day one. Without it, you're flying blind on a third of your deliverability picture.

Frequently asked questions