Subject lines are an important part of your email, so heres how to not mess them up. 

Your subject line is one of the most important parts of your email - its the first thing your customer sees and unengaging or boring copy wont entice many opens. Subject lines should be short ,snappy and engaging, and theres lots of ways you can do this. Although word count might be limited, it doesnt mean creativity has to be. This blog post will help you understand what makes a good subject line, as well as things to be weary of.

Personalize your content

Personalizing your content to your readers can increase open rates by 26%. So why not add it to your subject line too?

A few ways you can do this is by:

  • Celebrating an occasion:
    Hey Hattie, open for a birthday surprise >s
  • Send content based on behavior:
    Trains to London from →8, get this deal before it ends
  • Confirming a purchase:
    Hattie, your order is on its way!

Dont just use personalisation because you can. Whilst it might encourage a subscriber to open the email initially it doesnt mean they will click on anything after. You can measure this by A/B testing, and ensuring you arent adding personalisation just because. Make sure its relevant and is in-line with your brand.

Dont forget about preview text

Subject lines are important, but preview text is just as important as they help provide a little more information or context to your email. Both come as a package so take advantage of the additional space to entice the reader. Also, make sure your subject line and preview copy are different - they are one of the first things a reader sees, and display on a mobile notification screen.

A few ways you can do this is by:

  • Asking a reader to take an action (Uber): This also helps tell the reader what they need to do, Uber needs the reader to accept new terms before taking their next trip.
    • Subject line: Weve updated our user terms
    • Pre-header: Review and accept before your next ride.
  • Enticing your reader (Spareroom): By writing relevant content, in-line with your brand. Spareroom is asking readers how they really feel about housing prices rising.
    • Subject line: The real cost of living
    • Pre-header: Hows it affecting you?

Avoid using no-reply in your sender name

Steer away from using email addresses which are no reply e.g. These types of email addresses arent personal to the reader (it could be from anyone, or a bot) and they create a very one sided conversation. Instead use an actual name e.g. Elliot Ross ( or Elliot from Taxi Support. This creates a relationship with the reader, and if you are regularly sending email from this address, people will remember you better. Also, if a customer actually wants/needs to reply they can, instead of having to put in the effort to find a real email address.

Include emojis(but in moderation) d>=O<�=K<� @

64% of people say they open an email because of its subject line, so including emojis here can really help yours be noticed. They can improve open rates by 29% if used in the subject line! However, knowing your audience is important if you want them to do the legwork.

Heres a few good examples:

  • Are you reading for your flight tomorrow Hattie? 
  • < Summer fits have landed!
  • Up to 20% off our top restaurants

Check out our ultimate guide to emojis in email for more tips.

Dont shout at your readers

You might be excited about your sale or new product launching but it doesnt mean you should shout at your audience to promote it. Using all capitals isnt the best idea, it can come across as aggressive and spammy. So instead of saying SALE STARTS NOW, BE READY!!! switch this something friendly but still engaging e.g. � Our sale has landed! Heres your exclusive access.



Draw readers in with numbers

Sometimes numbers can do a lot of the talking for you, and they are really helpful when copy is limited. You can do this in a few ways:

  • Offering a discount:
    50% all winter fits until 9pm!
  • Providing an interesting stat:
    20% of people report housing prices are affecting their quality of living
  • Advertising a good price for something:
    Eurostar tickets to Paris from →20 per person this June



Amuse your reader

Humour is a nice easy way to engage with your readers. You can do this by injecting a joke, pun or bit of cheekiness into your subject line. It can help separate you from other people, and bring out your brands fun and cheeky personality. As long as it fits in with your brand of course, no one wants a dentist laughing at you about an outstanding dental payment. Ouch. Bit of a kick in the teeth.

Heres a few examples:

  • Let it flow, let it flow, let it flow >B>B
  • An eggcelent deal is waiting for you
  • We like being used
  • The names Post, SparkPost

Less is more with triggered emails

Dont overcomplicate your subject lines. For things like password resets, account setup reminders or order confirmations its best to keep them simple. Avoid emojis, extra copy or being vague. Be to the point. Order confirmation. Your order has been dispatched. Your item has been delivered.

Keeping them simple helps the reader navigate to them if they need to. For example if they have asked to reset their password and are in a rush, they need to be able to find the email right away. Dont make it hard for them!


Tease a release

Subject lines can create some real excitement or curiosity. For example, if you are signed up to the latest Nike Dunk release and you get the email at 8am, you want your readers to see the email and immediately respond.

A few subject lines which would work could be:

  • Just landed: Nike Dunk High Panda (limited edition!)
  • Pre-release of the new Nike Dunk for all Nike members
  • 24 hour Nike pre-sale → Low Dunk now in stock!


Test! And ask for feedback

And finally& test out your subject line. You can do this through A/B testing against different elements like text length, emotional language, emojis, or any of the elements mentioned above. And test over time - up to six months to properly see results. And dont forget to ask for feedback or help from your team. If you spend a lot of time on your email you might be burnt out and not think too much about the subject line so if you need a bump of creativity ask for help!

See how Taxi can help your team

Taxi helps marketing teams make better quality email, quicker, at a larger scale.

Let's set up a conversation�

44,916 email campaigns and counting.

Join the smart marketers using Taxi to make better email.