Connecting a custom domain to your GoHighLevel sub-account sounds simple — add a CNAME, wait for DNS to propagate, done. But in practice, especially for UK-based businesses using UK registrars, there are layers of gotchas that the US-centric tutorials never mention.

This guide covers the full UK setup: DNS records for your GHL sub-account, MX routing for inbound email, SPF/DKIM for deliverability, and the specific pitfalls to watch for with 123 Reg, GoDaddy UK, Namecheap, and Cloudflare.

Prerequisites

💡 UK-specific note: If you registered via 123 Reg, do NOT change your nameservers until you've exported your existing DNS records. 123 Reg wipes them on nameserver change — unlike most registrars. More on this below.

Step 1: Choose Your DNS Provider

You have two approaches:

For this guide, we'll assume Cloudflare (best for UK small businesses). If you're sticking with your registrar, the DNS records are the same — just skip the nameserver step.

Step 2: Add Your Domain to Cloudflare (Optional)

  1. Create a free Cloudflare account at dash.cloudflare.com
  2. Add your domain — Cloudflare will scan existing DNS records. Before confirming, export all your current records from your registrar as a CSV or take screenshots.
  3. Copy Cloudflare's nameservers (they give you two, like nancy.ns.cloudflare.com).
  4. Update nameservers at your registrar — this is the step that propagates. Expect 1–48 hours, though it's usually under 2 hours for .uk domains.

⚠️ 123 Reg specific: Their interface hides the nameserver change under "Manage Domain" → "Update Nameservers". They also have a bug where saved nameservers don't stick if you use their domain masking — disable masking first. Backup your records before changing nameservers. 123 Reg deletes all existing DNS records the moment you switch.

Step 3: Add GHL CNAME Record

This is the core record that points your custom domain to GoHighLevel. Go to Cloudflare (or your registrar) and add:

Type Name Target Proxy
CNAME @ (or your subdomain like app) ghl.your-subaccount.highlevel.com DNS Only (grey cloud)

🔥 Critical: Set Cloudflare proxy to DNS Only (grey cloud), not Proxied (orange cloud). GHL uses its own SSL termination and proxying through Cloudflare will break the connection. This is the #1 support issue we see from UK users who follow general Cloudflare tutorials.

The specific CNAME target varies by your GHL sub-account region. Your GHL support dashboard gives you the exact hostname during setup. For UK/EU accounts it's typically ghl.your-subaccount.highlevel.com — but confirm in your GHL Settings → Domains.

Step 4: Add MX Records for Email

If you want to receive email at hello@yourbusiness.co.uk through your GHL conversation inbox, you need MX records. GHL uses Zohomail natively for free sub-account email, but the DNS setup depends on your provider.

Option A: GHL's Built-in Mail (Zoho-powered)

Type Name Value Priority
MX @ mx.zohomail.com 10
MX @ mx2.zohomail.com 20

Option B: Custom SMTP (Mailgun, SendGrid, Google Workspace)

Most UK agencies prefer Mailgun for transactional email because it gives better deliverability analytics and dedicated IPs. The MX records will be provided by your email provider. Common setup:

Type Name Value Priority
TXT @ v=spf1 include:mailgun.org ~all —
TXT mailgun._domainkey k=rsa; p=MIGfMA0GCSqGSIb3DQEBAQUAA4G... —

You get the specific DKIM value from your Mailgun dashboard under Domains → your domain → DKIM.

Step 5: SPF, DKIM & DMARC — Why They Matter

Without SPF and DKIM, your emails from GHL will land in spam folders — or get bounced entirely. Google and Microsoft (including Outlook/Hotmail for UK users) now require both for any domain that sends more than a handful of emails per day.

SPF Record

Your SPF (Sender Policy Framework) record tells receiving mail servers which IPs are allowed to send email from your domain. A typical GHL + Mailgun SPF looks like:

v=spf1 include:mailgun.org include:spf.mandrillapp.com include:_spf.google.com ~all

For GHL's built-in Zoho mail only:

v=spf1 mx include:zoho.com ~all

🧠 SPF rule of thumb: You can have at most 10 DNS lookups in an SPF record (each include: counts as one, and some providers' includes themselves contain more includes). If you exceed 10, your SPF record becomes invalid and emails will fail SPF checks. Google Workspace alone counts as 1, Mailgun as 1, and Zoho as 1 — you're fine for most UK setups.

DKIM Record

DKIM (DomainKeys Identified Mail) adds a cryptographic signature to your outgoing emails. Receiving servers verify this signature against the public key published in your DNS.

Each email provider gives you a unique DKIM record. For GHL's built-in email, you'll find the DKIM values in Settings → Email Services → DKIM. Add the TXT record exactly as provided.

DMARC Policy (Advanced)

Once SPF and DKIM are passing, add a DMARC record to tell receivers what to do with unauthenticated email:

v=DMARC1; p=none; rua=mailto:dmarc-reports@yourdomain.com

Start with p=none (monitoring only), check your reports for a few weeks, then move to p=quarantine once you're confident all legitimate senders pass.

UK-Specific Gotchas

1. 123 Reg & GoDaddy UK Proxied MX

GoDaddy UK's premium DNS sometimes proxies MX records — this breaks email delivery. If you're using GoDaddy and email stops working after adding an MX record, switch to Cloudflare's DNS (free) or use @ with the correct priority value instead of @.

2. .uk Domains Propagate Slower with Some Registrars

.uk and .co.uk domains managed by Nominet don't propagate as fast as .com domains, especially with budget registrars. Don't panic if DNS takes 4+ hours. Cloudflare is noticeably faster for .uk domains.

3. LC Phone Numbers Require a Verified URL

If you're using an LC Phone (Twilio alternative) number for SMS, you must register your outbound URL in LC Phone's settings — a step most miss. Your custom domain must match the registered URL exactly, including the trailing slash. This is separate from the DNS setup and lives in LC Phone's console, not your registrar.

4. A2P 10DLC Registration for UK Numbers

If you send SMS from your GHL sub-account to US numbers, you need A2P 10DLC registration even from a UK company. The registration applies to your LC Phone or Twilio account, not your domain. The process takes 2–5 business days and costs roughly £3-4/month per brand. Your SMS will be blocked without it. See our LC Phone UK guide for the full A2P walkthrough.

Verification Checklist

After adding all records, use these free tools to verify before connecting to GHL:

⏱️ Propagation patience: DNS changes can take 1–48 hours. After updating, wait at least 30 minutes before troubleshooting. The most common "broken" setups we see are actually just propagation delays — especially on .uk domains with budget registrars.

The Bottom Line

Setting up a custom domain with GoHighLevel for your UK business is straightforward — but the US-centric tutorials miss the gotchas that trip up UK users. The key steps:

  1. Move your DNS to Cloudflare (free, faster propagation, better control)
  2. Set the GHL CNAME to DNS Only (not proxied)
  3. Add MX records for inbound email (Zoho if using GHL's built-in, Mailgun for better deliverability)
  4. Add SPF and DKIM to keep emails out of spam
  5. Register your verified outbound URL if using LC Phone for SMS

Most UK setups can be completed in under 30 minutes — plus DNS propagation time. The fastest path is Cloudflare + Mailgun, which gives you full control over DNS, SSL, and email deliverability without needing separate subscriptions.