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      6 Mins

      Don't Read This! Effective Email Subject Lines For Unbelievable Open Rates

      Don't Read This! Effective Email Subject Lines For Unbelievable Open Rates Featured Image
      Published on Jan 28, 2020 by Claire Blacker

      In 2019 the average business worker received 96 emails a day. That’s a lot of competition and it can be difficult to know how to make what you have to say stand out from the crowd. So the question is, how do you drive someone to open YOUR email?

      The answer? A perfectly crafted, well thought out subject line.

      Best practice for writing effective subject lines

      1. Keep it short and sweet

      You might have written the most hilarious, compelling or thought-provoking subject line but if the end is getting truncated, it becomes ineffective. Depending on device and email provider the maximum length of subject line ranges from 27-73 characters.

      2. Personalise your subject line

      No one likes to receive an impersonal email that has clearly been addressed to the masses. With a CRM full of good quality data - Noisy Little Monkey recommends HubSpot - you will be able to send emails personalised to the recipient, and your subject line can reflect this. 

      Why not start simple with the recipient’s first name? Then you can get even more creative with your subject lines depending on the information you have in your CRM.

      3. Tease your readers with an offer or discount

      People are suckers for free stuff or discounts on a product or service. Encourage recipients to open your email with the enticement of a juicy deal. Caution: don’t use this for every email you send, otherwise you’ll see diminishing returns… If you’ve got a specific promotion coming up, it’s a great way to see an immediate boost in your open rates. 

      4. Create urgency

      Try and command your reader’s attention by using urgent language that encourages them to take action. Make them feel as though if they don’t act now they’ll miss out on the action. Try phrases like ‘ending soon’, ‘don’t miss out’ and ‘only X days left!’.

      5. Use emojis

      Don’t be afraid to use emojis in your subject lines. They can jazz up your subject lines and are a sure fire way to make sure you catch your reader's eye. Just don't go overboard with them - one or two MAX is fine. A cautionary word of advice: not all email clients display emojis properly so stick them at the beginning or end of the text. This will also ensure people using screen readers can hear the subject line fully without interruption. 

      6. Use numbers

      There is quite a bit of research (here, here and here) that shows that using numbers in your blog titles increases click through rate, and the same reads true for email subject lines. In a sea of letters, numbers make your subject line stand out.

      7. Spark curiosity 

      Humans are curious by nature, so crafting a subject line that leaves a reader needing to know more is a sure-fire way to get your email opened. Do this by asking open ended questions like “how can you tell what your leads are thinking?” or make a controversial statement to get people hooked (note: whilst trying to be controversial make sure you aren’t being offensive!)

      8. Let the reader know what your email is about

      Whilst you’re trying to come up with the perfect subject line that ticks all the above boxes, you might lose sight of the main function of your subject line: to let the reader know what your email is actually about. After all, you should be sending your reader content that is going to benefit them in some way, so your subject line should reflect the value of your content.

      Download Now: Convert More Of Your Leads With This Buyer Persona Guide &  Template

      Examples of effective subject lines

      Obviously the purpose of your subject line will depend on the industry you’re in, the lifecycle of the recipient you’re sending your email to, and whether you’re B2B or B2C. However, hopefully the ideas below will prompt some inspiration for you no matter what your context is.

      Subject lines for sales emails


      This is a great subject line to use for a give / get sales email. For example, if you’re selling furniture, the surprise could be that the email contains “3 top tips for making your living room look bigger.” If they want to know more, they can book in a call with your Sales team. 


      Quick and snappy subject lines are effective for encouraging your prospect to take action. A short subject line like this one can be used if you need to get someone on the phone - although soften the subject line with a polite email such as “any chance you’ve got 15 minutes now for a catch up please?” Even if you don’t get the response you want, it’s better to know where you stand with a prospect. 

      Did you know… 

      … Noisy Little Monkey are a Diamond HubSpot Partner and can help companies like (insert name of their company) use HubSpot to sell more?

      Something like the above can work well! Intriguing the recipient in the subject line means they are more likely to open the email. Make sure to follow up by providing value in the email, otherwise they’re not going to reply, are they? 

      It’s ‘bye-bye’ for now, [Claire]

      Use this for re-engagement if your prospect isn’t getting back to you. Sometimes, they’re not interested and that’s fine. But sometimes, they’re just extremely busy so getting back to you isn’t the most important thing in the world.

      Potentially transformational email loading…

      Something like this is good for outreach. If you know that what you’re selling will genuinely help someone achieve their business goals, let them know in the subject line!

      There IS such thing as a free lunch, [Claire]

      Take your clients and prospects out for lunch if your company can afford to and guarantee it with a cheeky subject line like this. 

      Struggling with traffic?

      Do your research and find out how what you’re offering can benefit and add value to your prospect. Then focus on the challenge in the subject line. If it’s a priority, they’ll open it. 

      Subject lines for marketing emails

      3 days left to register! 

      This is short & sweet, includes a number AND conveys urgency. (Ha!) This type of subject line works best for events based emails, but would also work if there’s an offer or webinar.

      Wait, that can’t be right… 30% off sitewide? 

      Ecommerce, this one’s for you. Let the recipient know what offer you have on and use phrasing that exaggerates the weight of the offer. 

      LIMITED STOCK … get it before it’s gone!

      Another good one for ecommerce. The capital letters convey urgency and should encourage the recipient to take immediate action.

      Target Your Top Customers & Convert More Of Them Into Leads - Download the buyer persona guide here
      Psst… [Claire], here's something you'll be interested in

      Using the recipient's name in the subject line will make your email stand out amongst the masses. You're also teasing the content of what's inside - the only way they'll know if the email content is interesting to them is by opening it.

      They did WHAT to get more leads? 

      With this kind of subject line your reader will have to try incredibly hard to resist opening your email! It’s also short and sweet (tick!)

      Subject lines for service emails

      Uh-oh... Your subscription is about to expire 

      This lets your customers know that they need to act urgently, without using pushy language. 

      [Claire] here’s a 7 day free trial, just for you

      You’re checking two boxes here by offering your reader something, and making it personal. 

      How did we do? 

      Cut out unnecessary words and keep it short and sweet with a subject line like this. 

      [Claire], how did you find our lead nurturing guide? 

      This works well for a follow up email to a guide your customer might have downloaded from your website. Asking them a direct question with their name in the subject line makes this content conversational rather than the usual sales or marketing tone. 

      Tell us about your experience using [name of service/product] 

      This is a different kind of personalisation that refers to something the recipient has recently experienced. As it will be something familiar to them the subject line should catch their eye. 

      Urgent: Have we solved your problem? 

      Motivate your reader to take action by starting your subject line with a compelling word. 

      Hopefully these ideas have sparked some inspiration for you. Do you have a subject line which has worked really well in the past? Let us know on Twitter @noisymonkey!

      Claire Blacker

      Claire Blacker is Junior Digital Marketing Executive at Noisy Little Monkey.

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