Black Friday 2026: see who has started
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10:42
Synapse Retentionnow
Trellmoor Nutrition: test of “Black Friday early access: 20% off everything”: 3 problems to fix · 10:42
We checked a test email to the test address of Trellmoor Nutrition (trellmoor-nutrition.com).
5 things need you
In 4 of your brands, the most urgent first.
The subject line says 20% off, but the code TAKE15 gives 15% off.
Goes out today at 18:00
In the campaign “Black Friday early access”, before it goes out.
What to do: Make the subject line and the code give the same discount. Otherwise a subscriber who opens for 20% is given a code for 15%.
Then
Each opens where you fix it.
At 117 KB, its design is over the 102 KB at which Gmail cuts an email off.
Too many people marked “Welcome to Gorse and Gable: 15% off” as spam.
People who join through “Footer form” get no welcome email.
Next: connect its Klaviyo.
Where to go next
To fix
4
4 problems across 3 brands.
Test emails
6
In the last 7 days. 1 test found problems.
Reports
None yet
Each brand's report comes on the 1st of the month.
Market
38
This week's offers in the categories of your brands.
Fernwick Retention
Not ready yet: 3 things to fix
Fix them before the email goes to the whole list. The most costly first.
Subject and code disagree
The subject line says 20% off, but the code TAKE15 gives 15% off.
Subject line“Black Friday early access: 20% off everything”
In the email“Use code TAKE15 for 15% off your first order.”
What to do: Make the subject line and the code give the same discount. Otherwise a subscriber who opens for 20% is given a code for 15%.
One code, two discounts
The code DOUBLE10 is given two different discounts in one email: 10% off and 25% off.
Discount links without a code
The link “Shop early access” applies the code “CODE”, not a real code.
Fernwick Retention
No problems found. Ready to send.
A test can go out another way than the live send. So we don't judge its unsubscribe button or its proof it's from you.
Shared by Fernwick Retention. This page works until .
16seconds
From campaign to alert, in our one timed test
10 of 10
Planted mistakes caught
7,295
Emails read for the Market, from 687 brands. Counted .
8
Permissions in Klaviyo, all read-only
Our own test campaign, with mistakes we planted. The most costly first, in the alert’s own words. Point at one to find it in the email.
Black Friday early access: 20% off everything
Synapse Demo demo@synapseretention.com
To our address without a first name ·
Synapse Retention
Synapse Demo: 9 problems in “Black Friday early access: 20% off everything”
Proof it's from you
This email from synapseretention.com failed the check that proves it really came from you. Gmail says mail that breaks its rules may not arrive, or may land in spam.
What to do: Turn on a branded sending domain: it proves emails come from your web address.
Subject and code disagree
The subject line says 20% off, but the code TAKE15 gives 15% off.
What to do: Make the subject line and the code give the same discount. Otherwise a subscriber who opens for 20% is given a code for 15%.
Only in the copy to our address without a first name.
One code, two discounts
The code DOUBLE10 is given two different discounts in one email: 10% off and 25% off.
What to do: Give the code one discount everywhere, and check which one it takes at checkout.
Subject and email disagree
The subject line says 20% off, but the email says 15% off.
What to do: Make the subject line and the email give the same discount.
Only in the copy to our address with a first name.
Discount links without a code
The link “Shop early access” applies the code “CODE”, not a real code.
What to do: Put the real code in the link, where it says CODE.
Links that go nowhere
The link “View this email in your browser” goes nowhere: it points to “*|ARCHIVE|*”. It's how Mailchimp writes a fill-in field, which your platform doesn't fill in.
What to do: Point it at your email platform's own “view in browser” link, or take it out.
Links that may not open
Some email apps may not open the link “See everything in early access”: no https:// at its start.
What to do: Change it to https://www.synapseretention.com/early-access so every email app opens it.
Text subscribers shouldn't see
Subscribers see “*|FNAME|*” where their first name should be. It's how Mailchimp writes a fill-in field, which your platform doesn't fill in.
What to do: Use your email platform's own first-name field, with “there” for people without a name.
A greeting with no name
The greeting reads “Hi ,” for subscribers who didn't give a first name.
What to do: Give the name a fallback, like “there”, so it reads “Hi there,”.
Only in the copy to our address without a first name.
Every test, every scheduled campaign and every welcome email, checked as it arrives, without anyone asking.
Every brand gets one of ours. In Klaviyo, open the email’s “Preview” and type it in.
Click “Send test”, as you would to check the email yourself.
We check it the moment it arrives, and email what we found. Share it with your client by a link.
Start with the test address alone: your client connects nothing. To check scheduled campaigns and welcome emails too, connect Klaviyo or add our two addresses to the list.
The most urgent problem first, across all your brands. A store sees its own brand the same way.
Fernwick RetentionAgency portal
Free during early access.6 brands
Hhello@fernwick-retention.comOwner
Times are New York time.
Thursday 29 October
5 things need you
In 4 of your brands, the most urgent first.
The subject line says 20% off, but the code TAKE15 gives 15% off.
Goes out today at 18:00
In the campaign “Black Friday early access”, before it goes out.
What to do: Make the subject line and the code give the same discount. Otherwise a subscriber who opens for 20% is given a code for 15%.
Then
Each opens where you fix it.
At 117 KB, its design is over the 102 KB at which Gmail cuts an email off.
Too many people marked “Welcome to Gorse and Gable: 15% off” as spam.
People who join through “Footer form” get no welcome email.
Next: connect its Klaviyo.
Where to go next
To fix
4
4 problems across 3 brands.
Test emails
6
In the last 7 days. 1 test found problems.
Reports
None yet
Each brand's report comes on the 1st of the month.
Market
38
This week's offers in the categories of your brands.
Campaigns, your welcome, and the test emails you send us. Add our two addresses to your list. One has a first name and one doesn’t, so we see both versions of each email.
Which key automated emails are on. The offers in automated emails, and in scheduled campaigns every 15 minutes. Spam reports, bounces and unsubscribes. Every 2 hours we check that your store’s orders still reach Klaviyo.
What’s still open, what we no longer see, the offers you sent and how your market moved. As a page, and as a PDF. For an agency, it carries your name and logo.
Share a test’s result under your agency’s name, never ours. Your client sees it’s ready to send, or what to fix, before it goes out.
Your clients connect Klaviyo with a link you send. They approve on Klaviyo’s own page, and we only read.
Everyone in your team, at no extra cost. Each person is an owner, admin, member or viewer.
We read what we need to check your email, and nothing more.
Black Friday 2026
Each day we count the brands we follow: who has started, with what offer, and how early.
Each day to Mon 7 Dec, we counted who started, with what offer, and how early.
Open the Black Friday pageNo card needed. Paid plans start later, with a month’s notice.
Get early accessFor an agency
$199a month
Or $1,990 a year: two months free.
Up to 10 brands. Each brand after that is $20 a month, and never more than $399 a month in all.
Founding offer, until 15 December 2026
For your first three paid months, you pay only in months your team marked a finding “I fixed it”. Then you pay the normal price, locked for 12 months.
To take the offer, email hello@
Freelancers, and stores that run their own email: Starter is $79 a month, for up to 3 brands.
Prices are in US dollars, before VAT or sales tax. See what each plan includes
Klaviyo’s AI marketing agent, Composer, audits a campaign or an email when you ask it to. We check every test, scheduled campaign and welcome email as it arrives, without anyone asking. That includes whether the code matches the offer. And you see every client on one screen.
Not from us. Nothing we send goes to your client by itself: every email goes to people in your workspace. Your client sees a result only if you send its approval link, or invite them into your workspace.
Any. We check the emails themselves, so it doesn’t matter what sends them. Connecting an account works with Klaviyo.
Every email that reaches our two addresses: campaigns to their list, and your welcome. Reminders after a visit or an order don’t reach them. Connect Klaviyo, and we check those inside your account.
Yes. Each brand gets a test address of ours. Send the campaign’s test email to it, and we check it the moment it arrives. We email what we found to your workspace’s owners and admins. An agency can share it with its client, under the agency’s name.
Yes, every one that reaches us. When your welcome changes, ask for a welcome test. We give you a fresh address to add to your list. Then we check each welcome email arrives, and on time.
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