The 17 Email Signature DOs and DON'Ts

As an email signature management provider, we see a lot of signature templates. We see what a lot of companies get right and what they get wrong. So, in time-honored fashion, here's a checklist of the most important email signature best practices even the smartest users get wrong.

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  1.  Do Make It Social

    Social media plays an important part in the marketing mix – use customized email signatures to connect social with mail. Firstly, give contacts a taste of your content: put a recent Tweet or a blog post snippet (the whole post won't fit) under your signature.

    Then, add a social media icon so they can Twitter Follow or Facebook Share in a click. Unilever added a Follow link and went from 40,000 Followers to 235,000 in just 10 months – for free.

  2.  Don't Do It Yourself

    The number one mistake on signatures is inconsistency across a company; this is because every employee has made their own signature design. One might have a logo from 2014; another might be using a logo that’s 1,013 pixels wide; another using beside a misspelled email address.

    Use the same email signature template across your entire company. Make sure every signature matches a professional, stylish format that you've approved.

  3.  Do Use The Right Tools

    It sounds strange but keep in mind that this is an email signature: not a word document, not a web page, and not an image on its own. If you know HTML, code it accordingly – avoid some of the pitfalls we'll detail further on.

    If you don’t know HTML, don’t use Microsoft Word or Outlook to draw and edit your signature. These will format it in their own way: any other program may also interpret the layout differently and display it incorrectly.

  4.  Do Keep It Slim

    Whether it's in Gmail, Outlook or Apple Mail, very wide email signatures will not render well for a recipient.

    The industry standard for email signature size is about 650 pixels. We'd even say that a signature design should be a little thinner at 600px. This ensures nothing gets lopped off the edge of a message.

  5.  Do Use Tables

    For all your layout needs, turn to tables. Remember, you can make the borders transparent if you don't want to see a grid: we're just talking about using them to place each part of your design.

    Using tables means you'll know exactly how wide your signature template will be and that each element of the signature will appear in the right place. You don't have to worry about contact information getting squashed together or your company logo appearing inexplicably in the wrong spot.

  6.  Do Make It Simple

    Keep the layout as robust as possible – let the images and links make an impact, not the way they're arranged. If you try something over-the-top or ambitious, be prepared to back it up with lots of testing.

    In fact, if you have a decent way to test how it will look in lots of different email clients (Outlook, Apple Mail, Gmail), then be our guest. However, be sure that you create a signature that stays well-presented in all circumstances.

  7.  Don't Use Bullets

    Bullet points tend to render strangely from client to client – what Gmail thinks of as a bullet point differs from Outlook's definition. To ensure you conform to email signature best practices, just avoid bullet points altogether.

    If needs be, use different rows in your table to get that list look.

  8.  Don't Animate It

    Avoid animation in signatures. In most corporate email clients, you will not be able to watch an embedded video; you often won't even see the animations in GIFs.

  9.  Do Use Inline CSS

    This is more technical. Inline CSS and email HTML go hand-in-hand. A lot of standard, W3Schools-approved tags won’t work with the programs we use to read email.

    Get around them by using Inline CSS. If you’re not technical, use an online email signature generator or solution that will automatically turn your design into code that follows all these rules.

  10.  Do Write Full-Length HTML

    For the same reason, write out the email signature HTML code longhand. A lot of email platforms won't recognize the shortcuts you’re used to.

    For the non-developers among us, that means you shouldn’t just try to use a direct marketing email CMS or Word to build your template; as best practice, use an email signature management solution.

  11.  Do Use Images

    HTML images in email signatures are commonplace now, and most email clients display them without any major issues. You just need to decide how you want to be insert them into a template.

    You can either embed the image, so that a recipient doesn't have to download it, or host it on a web server and reference it via a URL. There are benefits to choosing one over the other; choose the method that works best for you.

  12.  Do Restrict Image Dimensions

    Don’t just rely on the size of the image being correct. You need to hardcode exactly how wide and high it will be in HTML. If you don’t, email clients like Outlook will render the image incorrectly.

    Again, for the non-coders reading this, that means you shouldn't just use a web CMS or Word to design your signature – it doesn't work like that.

  13.  Do Find The Right Ratio

    Try not to let the images overwhelm the text. Don't lose the email in that signature. It's hard. Every email is different: what looks right with blocks and blocks of text will look strange under a single sentence.

    Change how your signature looks on replies. The first email in a conversation may be longer, so a larger, bolder signature can make a professional first impression. Then, on replies, use a simpler, slimmer design to remind, not repulse.

  14.  Don't Forget Alt Text

    Remember image alt text – you never know where your mail may end up after it’s forwarded. With alt text, anyone who gets that email can hover over an image and get an idea of exactly what it does. We say ‘does’ rather than ‘is’ because each image in your signature tends to perform a function.

    A ‘Like Us on Facebook’ alt text on that social media link or a ‘Sign Up for Our Event’ on that banner for your upcoming exhibition explains what an icon offers. It makes your links a little more inviting.

  15.  Do Shrink Your Links

    Most links will be behind images – they're fine as they are. But when you have links visible in the signature – say a 'Web:' in your contact details – you'll want to keep them as short as possible.

    For many, that could be using great resources like and If you have a web admin, use a shorter URL and ask him to set up a redirect that takes visitors to the real page. This can then have as long and complex a URL as it needs with UTM parameters if required.

  16.  Don't Break The Law

    It's not exciting, but email disclaimers are required in many parts of the world.

    Like the Health Insurance Portability & Accountability Act (HIPAA) highlighting the need for an email disclaimer if you are a U.S. healthcare organization to the UK Companies Act stating all business emails must include certain business information, look into what laws apply to you and what’s needed to comply with them.

    Watch out for these regulations as best practice for your email signature templates; you never know when that new service you offer or that new market you've entered might take you into new legal territory.

  17.  Don't Worry

    Email signatures may be a massive asset, but they don't need to be a massive effort. There are a few smart ways to add a personalized signature design to all emails without bothering your IT department or your colleagues. Like choosing Exclaimer!

How Exclaimer Can Help:

If you're looking for an easy way to design and manage professional email signatures across your whole organization, we're here to help. Find out more or start your free trial today!

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