How to write email subject lines to avoid the spam folder [100+ templates]

Whether you send newsletters to an audience, cold emails to prospects, or any other emails to an audience: the first thing they see is your subject line.

A great subject line can:

→ increase your open rate

→ motivate your audience to reply

→ prevent your emails from landing in spam

Here are 5 proven tips you can use to create subject lines that catch your audience's attention and keep your emails from spam!

Tip #1. Personalize your subject line

A personalized subject line shows the audience that your email is written just for them! By talking to your audience directly, your email stands out from the hundreds of generic emails they receive daily. This makes them want to read your email, which boosts your open rates.

When your audience opens, reads & replies to your emails, you’re also less likely to get spam complaints which helps you keep a good sender reputation and avoid the spam folder.

Here are 10 variables you can use to personalize your subject lines:

Tip #2. Keep your subject line short & clear

Subject lines that are short, clear, and to the point catch your audience’s attention. By quickly showing your email's potential value, you motivate the audience to open it. The ideal length of a subject line is between 6 and 10 words.

Here are 5 questions you can ask yourself to write clear subject lines:

→ does my subject line focus on 1 clear idea?

→ does my subject line tell my audience: “what’s in it for them”?

→ does my subject line have at least 1 personalized element?

→ does my subject line avoid complicated words or jargon?

→ does my subject line match the content of my email?

Tip #3. Avoid spam words

Spam words and phrases can trigger email filters and land your emails in the spam folder. They also make your email look sales-y, which reduces your credibility as a sender. Your subject line should be natural and have a “nothing to sell you” approach!

Here are 5 tips to avoid writing subject lines that look like spam:

→ avoid writing subject lines ALL IN CAPITAL LETTERS

→ avoid generic subject lines – personalize them using the variables in tip #1

→ avoid using the same subject line for all contacts – A/B test them

→ avoid using too many special characters (%, !!,??) in your subject lines

→ avoid using any spam trigger words 👇

Tip #4. A/B test your subject lines

A/B testing helps you learn more about the tone your audience reacts to. The idea is to create two versions of your subject line with different angles and send each to 2 different audience segments.

Once sent, you can track the open rates, click-through rates, and replies you get for each version. This will help you decide which subject line was the most effective and tell you more about the tone your audience responds to.

By telling you more about your audience, A/B testing helps you write subject lines that are likelier to be opened.

Here’s an example of a subject line you can A/B test 👇

Tip #5. Make it actionable

Action-oriented subject lines tell your audience they will gain something tangible from your email. This could be a solution to a pain point, tips to achieve a goal, or a valuable resource.

Making your subject line actionable adds credibility and encourages your audience to take action. That could be opening your email or clicking on a link within it.

Actionable subject lines make your email stand out, as most people are used to receiving emails that make vague or unrealistic promises.

Here’s an example 👇

100+ subject line templates to get your emails opened

Your subject line can get your emails opened or marked as spam. So, following these best practices & using a tone your audience responds to is key to getting your emails read.

After sending 1000s of emails, we’ve cracked the code on subject lines that push people to open & reply to your emails. With that in mind, we created 100+ email subject line templates that you can use as inspiration for your email outreach!

Get the complete playbook here for FREE! 🚀 ⬇️