5 common email copywriting mistakes (and how to fix them)

Nobody’s immune to an email flop now and then. Here are five common email copywriting mistakes, handily coupled with some expert tips on exactly how you can neatly sidestep them. Bonus beginners' guide to A/B testing at the end!

1/ Tedious, one-size-fits-all subject lines

You hit send on “Monthly Newsletter” or “Quick Question,” then watch your open rate linger in single digits. Generic subjects don’t spark curiosity or promise value. Like that 'rocket'-shaped parcel you once got from creepy Uncle Pete, they stay unopened forever.

How to fix it

Brainstorm three variants before choosing one. Tap into numbers (“3 Tips for a Higher Open Rate”), questions (“Ready to Triple Your Email ROI?”) or urgency (“Last Chance: Your VIP Offer Expires Today”). Then A/B test the top two (scroll down for more info). A great subject line may get 80% opens. A crummy one – close to zero.

2/ Ignoring preview text (AKA the second subject line)

You craft a killer subject but leave the preview blank, so readers see “…and I hope you’re well” or something equally dull instead of a compelling segue into your artfully crafted missive.

How to fix it

Write a custom preview of 35–70 characters that complements your subject. Think of it as a movie trailer: tease the benefit or outcome. For example, if your subject is “Boost sales with this template,” your preview could read “Copy, paste and watch clicks soar.”

3/ Walls of text in the email body

Oh my good God, how copywriters love to write. Unfortunately, lengthy essays are rarely of interest to the average email opener (unless they are coming from – and I mean this literally – Stephen King). In fact, you’re basically paying your copywriter not to write if you want an email that people will respond to.

If  your email looks like a mini-novel, with no subheadings, no spacing and no bullet points, then expect engagement rates to be lower than a caterpillar’s belly-button.

How to fix it

Break copy into bite-sized chunks. Use subheads, emojis or bullets to highlight key takeaways. White space isn’t wasted real estate – it’s where readers rest their weary eyes before diving back in.

4/ Multiple competing calls to action

You mention “Download the guide,” “Book a call,” “Watch the demo,” and “Subscribe to our channel” all in one email. Your reader freezes, unsure which link to click.

Alas, they have entered the dreaded realm of decision paralysis, and faced with such a bewildering wall of choices, your dear reader picks nothing.

How to fix it

Focus on one primary CTA per email. If you must include secondary actions, de-emphasize them with smaller buttons or text links in the footer. Always ask yourself: what single action matters most right now?

5/ Skipping the final proofread (and tone check)

Typos may slip through. Your tone may wobble between formal, cheerfully chatty and best mate. Perhaps the message in the subject line doesn’t match the copy, or there’s a link in the text that’s no longer valid.

As with all copywriting jobs, the proof is in the proofing.

How to fix it

Read your email aloud or use a tool like Grammarly Pro. Double-check links and send a test email to yourself. If you have time, step away for an hour and return with fresh eyes, when errors are more likely to stand out like a bunch of sore thumbs in a bag.

Taking your strategy a step further with A/B testing for emails

As well as these five tips, a proven way to give your emails a stronger chance of landing is to A/B test them.

It sounds complicated, but actually isn’t. All you are doing is trialling either your subject lines or the email content (or various combinations of the two) on a small portion of your total email list to see which has the better response rate.

While this works well if you have a large email list, it isn’t really practical if you only have a few people to send your emails to.

But let’s suppose you have somehow built up an email list of 5,000 awe-struck followers, and it is time to send out an update that will rock their world.

Start by coming up with three completely different subject lines, and use each of these (along with your email message – don't leave it blank!) on 200 different names from within your 5,000-strong list.

If option A has 80 opens, option B has 40 opens and option C has 120 opens, then you know which subject line to use on the remaining 4,400 people (it’s C if you missed it. Come on!).

Trialling different content and CTAs

You can take your A/B testing even further by testing content variations, too.

Using your proven subject line, the next step is to send three different blocks of email copy and/or different CTAs to the next 100 people on the list.

If there is a clear winner, then the remaining 4,100 people will all receive an email that contains your best-performing subject line and your best copy/CTAs.

In this way, it’s easily possible to improve your success rate by 40% or more.

Written by Mike Peake, UK freelance copywriter, email copywriter and website content writer.

E: hello@bymikepeake.com

T: +44 (0)208 133 4306

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