Cold email A/B testing that picks winners by replies, not guesses
Most advice about cold email is somebody else's opinion about somebody else's market. ColdReach lets you test your own subject lines, first lines and bodies against each other inside a live sequence and see which version earns more replies from your own prospects. The result comes from your data, not from an industry average.
Subject lines, first lines and bodies
Each email step in a sequence can carry more than one version. ColdReach splits the prospects of that step between the versions and keeps every other part of the step the same, so the difference you see comes from the part you changed.
- Subject lines: short against long, question against statement, with or without the company name
- First lines: a line about the prospect's website against a line about their role
- Bodies: a short ask against a fuller explanation, one call to action against another
Tests split by step
A test belongs to one step. You can test the subject of the first email and the body of the second follow up in the same sequence, and each test reports on its own. Prospects keep the version they received when the thread continues, so a follow up never contradicts the email before it. Build the steps themselves with our email sequence software.
Winner by reply rate on your own data
ColdReach measures each version by reply rate, counting the replies that the prospects of that version sent back. Reply categories from the unified inbox for cold email show you whether a version brought interested replies or mostly not now and out of office notes. When you are confident in the result, you keep the winning version and the step continues with it for every new prospect.
- Sent, replied and positive replies for every version side by side
- Results per step, so one strong subject line does not hide a weak body
- No borrowed benchmarks, only the numbers from your own sends
Why reply rate and not open rate
Opens are an unreliable signal because many mail clients load images automatically or block them. A reply is a person answering you. That is why ColdReach treats replies as the measure that decides a test, and why our cold email analytics center on replies, positive replies and meetings.
AI-written versions you approve
AI models can write the alternative versions for you. ColdReach reads each prospect's company website and writes a first line and body in your voice for every version, and by default a person on your team approves the drafts before the first send. You test ideas, not just wording, without writing every variant by hand. Our AI SDR page shows how the research works.
Fair tests need clean sending
A version can only win on replies if its emails reach the inbox. ColdReach verifies addresses before a prospect enters the sequence, sends from your own connected mailboxes with ramp-up, rotation and daily caps, and pauses a mailbox when bounces or complaints rise. Read more on email deliverability.
Which plans include full A/B tests
Starter includes subject line tests. Growth, Scale and Enterprise include full tests of subject lines, first lines and bodies on every step. Growth costs $149 a month, or $74 a month billed yearly. See every limit on our cold email software pricing page.
Questions
What can I test on the Starter plan
Starter tests subject lines. Tests of first lines and bodies are part of Growth, Scale and Enterprise.
How does ColdReach decide which version wins
Each version is measured by reply rate on your own prospects, with reply categories alongside, and you keep the version that performs better for the step.
Can I run tests on several steps at once
Yes. Each test belongs to one step, so you can test different parts of different steps in the same sequence and read each result separately.
Do prospects see both versions
No. Each prospect receives one version of a tested step, and follow ups in the same thread stay consistent with it.
Find out what your prospects answer
Add a second version to your next step and let your own replies settle the question.