Benchmarks / Email length

How long should a cold email be?

Based on 850 million+ emails · Smartlead platform data

Under 50 words. First emails under 50 words earn a 1.47% reply rate, one reply per 68 contacts. The weakest length is 100 to 149 words, at 1.03%, or 97 contacts per reply.

Cold email reply rate by length

Reply rate for first emails, grouped by word count. Built from more than 850 million emails sent through Smartlead.

First email length	Reply rate	Contacts per reply
Under 50 words	1.47%	68
50 to 99 words	1.35%	74
100 to 149 words	1.03%	97
150 to 199 words	1.31%	76
200 words or more	1.18%	85

What the data shows

The shortest emails win. Under 50 words earns 1.47%, ahead of every longer band, and 50 to 99 words comes second at 1.35%.

The worst length sits in the middle. Emails of 100 to 149 words earn 1.03%, lower than emails twice their length. Cutting one of those emails to under 50 words takes it from 97 contacts per reply to 68.

Longer isn't always worse. Emails of 150 to 199 words earn 1.31%, well ahead of the 100 to 149 band, though still behind the shortest emails.

How this compares with common advice

Published guides recommend anything from 20 to 50 words up to 50 to 125 words for a first cold email. The data backs the short end. The 100 to 149 word band, the weakest in the data, overlaps the top of the 50 to 125 word range several guides recommend.

What this data can't tell you

It counts words, not what the words say. It doesn't measure subject lines, formatting or relevance, and it can't show why 150 to 199 word emails do better than 100 to 149 word ones.

How to use these benchmarks

Write the first email in under 50 words, with one point and one ask. The cold email writing guide covers the structure.
If a draft lands at 100 to 149 words, cut it down rather than padding it out.
Spend the words on relevance. The median sender puts a custom variable in 75% of emails, and a short email leaves room for one.
Put the effort into email one. The first email earns a reply every 85 contacts, and the seventh needs 303.
Send it in the morning. Reply rates peak between 6am and 10am in the recipient's time zone.

Frequently asked questions

How long should a cold email be?

Under 50 words for the first email. That length earns a 1.47% reply rate, one reply per 68 contacts. The weakest length is 100 to 149 words, at 1.03%.

Is 200 words too long for a cold email?

It is longer than it needs to be. Emails of 200 words or more earn 1.18%, against 1.47% for emails under 50 words. They still beat the 100 to 149 word range, which earns 1.03%.

What is the 12 second rule for emails?

It comes from Litmus research finding that people spend about 12 seconds reading an email on average. It is a reading-time figure, not a word count, but it points the same way as the length data. Make the point fast.

Methodology

More than 850 million emails sent through Smartlead, using combined, anonymous platform data only. Only senders with at least 500 emails sent in the period are included. Each first email is grouped by its word count.