Every single element of an email – from the permission notice to the footer – plays a critical part in making it to the inbox. However, one carries even more responsibility in getting your message in front of your recipients: your subject line.

Short and difficult to manage, this tiny span of less than 100 characters is what your customers and their email clients will see first of your email, sending you on to your customer's inbox or the much-maligned junk file. That's why perfecting it is mandatory if you want your email marketing campaign to be a success. Here are 6 ways to do that.

Clearly defined objectives set the tone for effective subject lines. Here are some examples of clairvoyant goals, which can be used to write impactful subject lines:

By defining your goals early on, you help set the tone for subject line testing. Research indicates that readers are likely to find shorter subject lines more credible. Try and keep your subject lines simple and short – preferably four to seven words. You're excited about your product and you want your recipients to feel the same: it's a fact. But there is a fine line between stirring up excitement and just plain hyping up a product to your customers. Your subject line should speak to the good qualities of your product or service, but avoiding going overboard and making it seem like the end-all-be-all of everything out there. Customers are more shrewd than ever before and they can tell when someone is overdoing it. For this reason, keep your subject line intriguing and exciting, but not too over the top. Certain words and phrases create a negative impression in the readers’ mind and might guarantee instant deletion of messages. Avoid using the following words in your subject lines or your email messages:
Also, don't start your subject line with any of these words:
If you use an Email Service Provider (ESP) like Benchmark Email to send your email, it has a ‘Spam Checker' tool available for checking your Spam Score for each email campaign. Various recent studies show that email campaigns featuring brand names in subject lines tend to have higher open rates. Use this stat to your advantage. If you're promoting three different products, pick the most popular one and feature it in your subject line. You may be surprised at how simple and effective this trick actually is. If writing your latest email subject line has you tied up in knots, go for the obvious: a generalized description of what your email is or what will be found in it. For instance, “Benchmark Email Bulletin, June 26” is as basic as you can get when it comes to subject lines, but it tells the recipient, probably in the middle of wading through hundreds of spam emails, that your message is the real deal. A straightforward, honest subject line tells recipients that your email, when opened, delivers familiar, trusted content.