ListDefender is a protection layer built specifically for HighLevel agencies to block bots on forms, continuously scan and clean contact lists, and protect sender reputation — before deliverability problems start.
If you run HighLevel for clients, bots, form spam, fake leads, and low-quality sign-ups can quietly poison contact lists and damage email deliverability across multiple clients.
Most agencies don't realize the damage until inbox placement drops, campaigns underperform, or clients start asking why leads stopped converting.
ListDefender adds a HighLevel-specific protection layer that blocks bad data at the form level, runs continuous list scans, and preserves sender reputation — before problems surface.
HighLevel does a great job managing funnels, automation, and client workflows — but like every platform, it cannot fully stop adversarial abuse at the edge. Even the built-in paid validation in HighLevel provides very minimal protection.
That's where agencies get hurt.
Native protections are designed for usability, not for active abuse and coordinated attacks.
ListDefender protects HighLevel agencies with three automated layers, working together continuously.
Blocks bots, fake sign-ups, disposable emails, and junk submissions before data ever enters HighLevel. ListDefender goes beyond basic validation with advanced quality checks that detect form stuffing and bypass attempts automatically.
Runs your first full scan immediately, then performs ongoing SmartScans to keep HighLevel lists clean, deliverable, and safe to send to.
ListDefender continuously monitors engagement and automatically manages contact status over time. As contacts engage or disengage, they are moved between safe-to-send and suppressed states — so you always know who belongs in your sends and who doesn't. This protects inbox placement and sender reputation without manual segmentation.
Securely connect ListDefender to your HighLevel account in seconds.
ListDefender scans your database while blocking bots on forms in real time.
Dozens of scans run each month to protect long-term deliverability.
ListDefender exists because real businesses were attacked.
Coordinated bot traffic flooded forms, polluted contact databases, and quietly damaged deliverability across multiple systems.
Those failures exposed the gaps ListDefender was built to close.
That's why agencies rely on it before problems surface, not after damage is done.
ListDefender is designed for:
If client inboxing matters to your reputation, this is infrastructure — not an add-on.
ListDefender's Agency Program is built for scale.
Make list and deliverability protection part of your standard agency stack.
"Welp...I happened to notice some weird stuff going on with contact id's. We've spanned hundreds already this morning, which makes no sense. So I look at how many spam submissions have already been filtered today. Already 2k just this morning. Nearly 100k in the past 30 days. Holy crap. Thanks so much for building this tool!"
"ListDefender Saved Our Business! Our email deliverability plummeted and our business was slowly being choked out and no one could identify what was going on. ListDefender identified the issue immediately and stopped the bots, removed the bad accounts, and got us back on track. What ListDefender accomplished in hours, Klean13 and multiple tech agencies couldn't do at all. We won't run our business without it again."
"I do want to say, it is STAGGERING the amount of bots ListDefender is catching....lol. Look at this image with the sheer number and you can see the list of bot submissions. We are in the middle of a big promo and generating a lot of leads and WOW, just WOW!"
"ListDefender has given us a clear & accurate view of the contacts in our CRM. It's helped protect our reputation by identifying bots and reducing spam complaints, keeping our deliverability strong and our lists healthy. Maintaining this level of visibility and control used to be nearly impossible; now I couldn't imagine operating without it."
Your agency's reputation depends on clean data and reliable inbox placement.