Free for 100 brands · Q4 2026

Your campaigns are landing in Promotions. We move them to Primary.

One integration with Klaviyo. No rewrite of your copy, your design, or your sending schedule. Then a holdout group proves exactly how much it was worth.

Claim a free spot See how it works
Setup takes about five minutes. Results on your next campaign.
Your customer's inbox

Illustrative. Your actual placement is measured per campaign against a holdout group — see below.

How it works

Three steps. Nothing you write has to change.

The Promotions tab is a classification decision Gmail makes before your customer ever sees the email. We change what that classifier sees — not what your customer reads.

STEP 01

Connect Klaviyo

One integration, read and write scoped to campaigns. About five minutes, no developer required.

STEP 02

We optimise the send

Applied automatically to each campaign as it goes out. Your copy, design, offers and schedule stay exactly as they are.

STEP 03

A holdout group proves it

A slice of your list is deliberately left untouched, so the difference between the two groups is attributable to us and nothing else.

The part most tools skip

If we can't prove it worked, it didn't.

Any vendor can point at a rising open rate and take credit for it. Seasonality moves open rates. A good subject line moves open rates. The only way to know what we did is to run the same campaign both ways, at the same time, to the same kind of people.

Optimised — 90% of your list
Campaign goes out with Primary applied

Same subject line, same creative, same send time.

Holdout — 10% of your list
Campaign goes out untouched

Randomly assigned, statistically comparable, deliberately left alone.

The gap between those two groups — in opens, clicks and revenue per recipient — is the number we report. It is the only figure that survives the question "how do you know it was you?" And if the gap is zero, we tell you that too.

What it's worth

Put your own numbers in.

Placement is a multiplier on every campaign you send between now and December 31st.

$
+60%
Incremental Q4 revenue $132,149 From 1,050,000 sends currently opening at 18.4%.

Your numbers, our arithmetic, shown in full: sends × the open-rate gain you set × a 10% click-of-open and 12% purchase-of-click rate × your AOV. Tools in this category publicly claim 50–100% open lift; the slider starts at the conservative end. This is a model. The holdout group replaces it with your real number.

Versus the alternatives

Same outcome. Fewer hoops.

 PrimaryMaverickMailmend
What it isInbox placement, and only thatOne of three products, behind an AI-video homepageInbox placement
To see pricingOn this pageBook a demoBook a demo
To get startedForm, no callDemo callDemo call
Holdout proofEvery campaignYesNot stated
Q4 2026 costFree, first 100 brands2-week trial, then paidQuote on request

Comparison reflects publicly available information on each company's own website as of September 2026.

The offer

Free for 100 brands, through Q4.

Not a trial that converts to a charge. Not a demo call to find out the price. Free through December 31st, for the first hundred brands that take it.

01
Inbox placement on every campaign

Applied automatically once Klaviyo is connected. Nothing to remember, nothing to paste per send.

Included
02
Holdout measurement, per campaign

Opens, clicks and revenue per recipient for both groups, so the lift is attributable rather than asserted.

Included
03
A placement read before we start

Where your campaigns land today, per provider, so there is a baseline to measure against.

Included
04
Turn it off whenever

Disconnect in one click. No contract, no notice period, nothing to cancel.

Included
Your cost through December 31$0
Why it's free

We need proof more than we need your money.

Primary is the first software Growth Legend has brought to market. We've been fixing email programs by hand as a service for years; this is the part we finally turned into a product.

It's new, and almost nobody has heard of it. A hundred brands with a measured holdout number going into 2027 is worth more to us than anything we could buy with an ad budget — so we're spending Q4 doing the work instead of marketing it.

You get the placement lift and the measurement. We get to ask for a testimonial if the number is good, and to hear about it if it isn't. That's the whole arrangement.

The cap is capacity, not scarcity theatre. Each account takes real setup time, and there are only so many weeks left in the quarter.

100 spots · 65 days to Black Friday

Claim a spot.

Two fields. We'll come back within one business day to connect Klaviyo.

Primary — Q4 Founding 100

100 left
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No card. No demo call. Disconnect any time.

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Confirmed against

  • Right nowYour spot is held. Nothing else needed from you.
  • < 1 business dayWe email you a Klaviyo connect link. Five minutes, no call.
  • Next campaignPlacement optimisation applies automatically, with a holdout group set aside.
  • 48h after thatYour first holdout report: opens, clicks and revenue per recipient, both groups.

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