Got an idea? Discuss it on WhatsApp — right now, no forms Negotiate directly — message us, agree a price, get started today Single emails from £95 · flows from £295 · fixed quotes Free advice on your email programme — just ask Tested in 60+ email clients · Klaviyo & Mailchimp · same-day replies
Home/Guides/The email testing checklist
Guide · UK

The email testing checklist

Written by the studio that designs and codes these emails every week — with real examples from client programmes.

Real email design from our portfolio related to this guide
In short

Before any send: verify the primary CTA, preheader, alt text, dark mode, mobile stacking, sub-100KB weight, live links, merge-tag fallbacks and the correct segment. The full point-by-point checklist is below.

Run this before anything ships. It's the condensed version of the QA process we run on every client email — each point exists because skipping it has burned someone.

Design & content

  • One clear primary CTA, visible without scrolling
  • Preheader text written (not defaulting to random body copy)
  • All copy proofread in situ, not just in a doc
  • Images have descriptive alt text
  • Unsubscribe and legal footer present and readable

Code & rendering

  • Tested in Outlook (Windows), Gmail (app + web) and Apple Mail minimum
  • Dark mode checked — logos, backgrounds and text contrast
  • Mobile stacking order verified on a real device
  • Total email under ~100KB to avoid Gmail clipping
  • All links clicked and UTM-tagged correctly

Platform

  • Merge tags previewed with real data, including missing-data fallbacks
  • Correct list/segment selected — check twice
  • Test send reviewed by a second person

Want this done for you every time? Our service includes full QA on every email.

£95 / fromSingle email — designed, coded, tested & uploaded
£295 / fromFlow package — 3–5 emails, connected in your platform
See pricing →
60+Email clients tested
41Real emails in portfolio
£95Single email, from
24hFixed quote turnaround
Related work from the studio
Editorial newsletter email design
Nonprofit welcome email design
Welcome series email two — brand story design
Abandoned cart email two — objection handling design
Browse abandonment follow-up email design
Win-back email design for lapsed customers
Klaviyo flow email two — social proof design
B2B case study email design
Limited edition product drop email design
Community spotlight email design
Editorial newsletter email design
Nonprofit welcome email design
Welcome series email two — brand story design
Abandoned cart email two — objection handling design
Browse abandonment follow-up email design
Win-back email design for lapsed customers
Klaviyo flow email two — social proof design
B2B case study email design
Limited edition product drop email design
Community spotlight email design
Real work

Straight from the portfolio.

Real email related to email testing checklist from a client programme
Klaviyo welcome flow email from a real programme
Fashion campaign email from a real programme

See the full case studies →

Honest comparison

Your options for email testing checklist, compared.

Template galleriesCheap marketplacesEmailDesign
Custom design (not a reskin)✗✗✓
Hand-coded, tested HTML✗Rarely✓ 60+ clients
Outlook & dark mode handled✗✗✓
Set live in your platform✗Extra cost✓ Included
Fixed quote before work startsn/aVaries✓ Always
One accountable studio✗✗✓
Platforms

Built for the platform you already use.

KLAVIYOMAILCHIMPSHOPIFY EMAILOMNISENDHUBSPOTANY ESP · RAW HTML

Every project is designed for your platform's editor and set live in your account — see Klaviyo email design or Mailchimp templates.

Deliverables

What you receive with the done-for-you version.

Custom design files (Figma) — yours to keep
Hand-coded, commented HTML files
Render-test report across 60+ email clients
Dark mode & Outlook verification
Upload & setup in your email platform
Mobile-ready responsive build
Accessibility & alt-text pass
Post-launch tweak round included
Who is EmailDesign?

A UK email design and development studio. We design custom emails, hand-code the HTML and set everything live in platforms like Klaviyo and Mailchimp — from £95 per email.

Can you do this for us?

Yes — this topic maps directly to our services. Get a fixed quote within one working day.

Ready when you are.

Tell us what you're sending and where — fixed quote within one working day.

WhatsAppGet a quote →
Got an idea? Let’s discuss →