You've been running a cold email campaign for three weeks. Response rate is sitting at 0.8%. Your inbox has crickets. You're starting to wonder if you should just kill it and try something else.

Here's what most people get wrong: they kill campaigns too early, or they let them rot too long. Both cost you money.

The decision to kill a campaign isn't about gut feeling. It's about numbers. And there are specific thresholds that tell you whether a campaign is genuinely broken or just needs more time.

How Long Should You Actually Run a Campaign Before Deciding?

This is the first mistake people make - they don't give campaigns enough volume to make a real decision.

You need at least 200-300 emails sent before you can tell anything meaningful. That's the minimum. At lower volumes, variance kills your judgment. You might kill a 2.5% response rate campaign because you got unlucky with your first 100 sends.

For a typical cold email campaign sending 50-100 emails per day, that's roughly 3-5 days of volume minimum. I'd actually recommend 500+ emails before you make a final kill decision on copy/positioning. That's about a week of sends for most operations.

But here's the nuance: if you're hitting serious infrastructure problems (high bounce rates, domain warming issues, spam folder placement), you'll see those signals faster. Those show up within 1-2 days usually.

The Three Metrics That Actually Matter

When you're evaluating whether to kill a campaign, look at these three numbers. Not opens. Not clicks. These three.

1. Bounce Rate

Hard bounces above 5% mean something is wrong with your list or infrastructure. Soft bounces above 8-10% suggest domain reputation or warming issues. If you're seeing bounces in these ranges after 300+ sends, something is broken and you should pause and fix it before deciding on the campaign itself.

What you're looking for: Hard bounces under 3%, soft bounces under 6% after your first 500 sends.

2. Reply Rate

This is what actually matters. Not open rate - replies.

Benchmarks for B2B cold email:

The key word here: after 500 sends. Don't judge reply rate on 100 emails.

3. Conversion Rate (Reply to Close)

This one changes everything. You might have a 1% reply rate but convert 60% of replies to calls. That campaign is actually gold.

Track how many replies turn into meetings or qualified conversations. If you're converting 40%+ of replies into actual sales conversations, your campaign is working even if reply rate looks weak. Keep it running.

If you're getting replies but converting 10% or less, your positioning was wrong or your follow-up is broken - but the email itself is working.

The Kill Decision: Five Specific Scenarios

Kill the Campaign If:

1. Below 0.3% reply rate after 1,000 sends - You're not resonating. The list, offer, or positioning is wrong. Time to rebuild.

2. You're getting spam complaints on 20+ emails - Your domain reputation is tanking. Pause immediately and fix infrastructure. This will damage your sending ability long-term.

3. Hard bounce rate climbs above 7% after 500 sends - Your list source is bad or data is stale. Getting replies isn't worth the domain damage.

4. You've tested three different angles and they all sit below 0.5% after 500 sends each - Your target audience either doesn't have the problem, or you're talking to the wrong persona. Move on.

5. Reply rate is strong but conversion is under 5% - This is a follow-up or qualification problem, not an email problem. Don't kill it. Fix your process. (See what to look for in a campaign review for this level of diagnosis.)

Keep the Campaign If:

1. Above 0.8% reply rate at any volume - This is working. Scale it.

2. 0.5-0.8% reply rate and you haven't hit 1,000 sends yet - You probably have enough data. But if you can keep sending at your current pace, get to 1,000 before deciding. Volume kills doubt.

3. Replies are qualified even if volume is low - If 60%+ of your replies are actual prospects asking real questions, that email is resonating. Keep sending, even at 0.6% reply rate.

4. You identified the problem and can fix it - Wrong persona? Change targeting. Copy not landing? Test a new angle. Domain warming issues? Pause and warm. Don't kill - repair.

The Real Tell: Does Your Bounce + Spam Rate Make Sense?

Here's a filter that saves time: if your bounces and spam complaints combined are under 8-10% of total sent, your infrastructure is fine. The campaign itself might just be weak.

If your bounces + spam complaints are 15%+, don't judge the campaign yet. Fix infrastructure first, then rerun the same email to a fresh segment.

When to Pause Instead of Kill

There's a middle ground a lot of people miss. You don't always need to kill a campaign. Sometimes you just pause it.

Pause (don't kill) if:

Pausing keeps your domain healthy and gives you the option to reactivate without starting over.

The Gap Between Knowing This and Actually Executing It

Reading this, you can make a kill decision on your own. But actually tracking these metrics across 500+ emails, testing different variables, managing domain reputation while you're doing it, handling replies in real-time, and deciding on relaunch strategy - that's a different project. It requires infrastructure, tracking setup, and someone who knows what to look for when things go sideways (and they always do). That's the part most in-house teams underestimate.

Related Guides