HighLevel Bounce Suspension and Domain Warm-Up: The Numbers and How to Avoid a Lock

HighLevel warns at a 3% bounce rate and blocks LC Email sending at 5%: two 12-hour blocks, then a permanent one that only Support can lift. Since August 2026 the lock needs at least 500 sends and 25 bounces to trigger. The way most sub-accounts get there is an old or imported list sent in one go, often to fill a warm-up stage. Check the list before the campaign, and don't push volume to move stages.

These numbers come from HighLevel's own help articles, read on 3 November 2026. They change, so check the linked pages before you rely on them.

The bounce lock, step by step

From HighLevel's bounce suspension article (modified 17 September 2026):

Stage	Bounce rate	What happens
Healthy	0 to 3%	Nothing
Warning	3%	Pre-block warning email
First block	5%	Sending blocked for 12 hours
Second block	5% again	Another 12-hour block
Third block	5% again	Permanent; Support has to lift it

The 13 August 2026 update changed when the lock can start: a "tiered minimum send floor: 50 → 500", and "at least 25 bounces must occur before the system considers locking". A small test send can't trigger it any more; a real campaign to an old list can.

HighLevel's separate sending health guide sets stricter targets for day-to-day health: bounces below 2%, complaints below 0.1%, opens above 15%. Treat 2% as your working ceiling and 5% as the wall.

How the domain warm-up works

HighLevel's fixed-stage warm-up guide (modified 30 June 2026) describes 15 stages, from 1,000 emails a day at Stage 1 to 250,000 at Stage 15. The rules that matter:

• It starts on its own for new dedicated domains once they're created and verified. Existing domains need Start Warmup under Settings > Email Services > SMTP Service > Dedicated Domain and IP.
• You move up only by sending the full daily limit for the current stage. Falling short keeps you where you are.
• Missed days don't penalise you. They "just pause progress".
• Hitting the limit doesn't block sending. Mail still goes out.

The first rows of the table:

Stage	Daily limit
1	1,000
2	2,500
3	5,000
4	6,500
5	8,000
6	10,000

The email sending guide adds hourly pacing for the early stages (100 an hour at Stage 1, 300 an hour at Stage 2) and says to send only to opted-in contacts likely to engage during warm-up, not cold email.

Why filling a stage with an old list backfires

The progression rule creates a temptation: to get from 1,000 a day to 2,500, you need a full 1,000-email day. A small business may only have 400 engaged contacts, so someone exports the whole sub-account, two years of form fills and imports, and sends to all of it.

That list is where the bounces are. Addresses typed wrong on a funnel, throwaway emails from a lead magnet, and work inboxes closed since. At 1,000 sends, 50 bounces is 5%. That's a block on the same day the stage was supposed to advance.

The guide's own advice points the other way: stay in a stage if your engaged volume is lower. Moving up a stage is a capacity number, not a reputation score.

Before the campaign

1. Export the list you plan to send to, with DND visible. Our guide to exporting GoHighLevel contacts to a clean list has the steps.
2. Set aside DND, duplicates and role addresses. HighLevel's health guide also says to avoid info@, admin@ and noreply@. The GoHighLevel contacts to email list tool does this in your browser.
3. Check the addresses. Upload the list at /verify and import only the valid file back, tagged. Or turn on HighLevel's Email Verification Service with first-send validation; its article mentions re-validation every 90 days.
4. Send to recent openers first. HighLevel's recovery steps use people who opened in the last 30 days, and widen only once the rate is back under 2%.
5. Watch the first day. The bounce rate calculator turns the campaign's numbers into a rate you can compare with 3% and 5%.

If you're already blocked

• Temporary 12-hour block: pause campaigns to the full list, export and suppress the bounced contacts, and check the rest before sending again. HighLevel says enabling its Email Verification Service can also lift the block.
• Permanent block: open a ticket with the sub-account ID and a screenshot of the error. HighLevel says permanent unblocking "cannot be automated" and approval isn't guaranteed.
• Afterwards: HighLevel's guide says significant reputation recovery can take 4 to 8 weeks of healthy metrics. Our post on what to do after a high bounce rate covers the general recovery order.

Where SimpleVerifier fits

SimpleVerifier checks the list before it goes back into HighLevel, or inside a workflow as contacts arrive (see the HighLevel workflow guide). It doesn't change HighLevel's thresholds or lift a block. The first 100 checks are free with a Google sign-in on the verify page. Pro is $39 a month with the first 100,000 checks a month at full speed, then slower, never cut off, and one-time packs of 10,000 checks for $15 never expire. See pricing.