Brand Consistency in Email: Style Guide Essentials
The eight decisions a style guide has to settle so that three people writing email produce one voice.
On this page
The short version
- Eight decisions settle almost every recurring argument about an email. Writing them down is what makes three people sound like one sender.
- The guide has to cover voice, not only visuals. Visual consistency is the easy half and the one that gets documented.
- Anything the guide does not decide gets decided per send, by whoever is writing, differently each time.
A brand guide for email is not a smaller version of the company brand book. The company book covers colour, type and logo usage; it almost never covers whether you use contractions, how the from name is written, or what the sign-off is.
Those are the decisions that make email feel consistent, because email is read as though a person wrote it. Two writers with the same colour palette and different habits produce two obviously different senders.
The eight decisions
Each of these gets settled once and referenced thereafter. The value is not in any individual choice — it is in not relitigating it every fortnight.
What to settle
The from name, exactly
Company, person, or person at company. This is the most visible identity signal you have and it should not vary by send. Changing it resets the recognition you have built and can affect placement, because engagement history attaches to the sending identity.
Who is speaking
First person singular, first person plural, or neither. "I" and "we" produce different emails, and mixing them within one programme reads as inconsistent even when nobody can say why.
Formality, with an example
Contractions or not. Whether you address the reader as "you" throughout. One paragraph written the approved way is worth more than a page describing the register.
Subject line conventions
Sentence case or Title Case. Emoji or not. Whether prefixes like "[Newsletter]" are used. These are visible in the inbox list, which makes them part of the identity rather than a style detail.
The type scale
Sizes for body, headings and footer, with the minimum stated. Two writers picking heading sizes by eye is how a template quietly acquires five of them.
Colour, with the roles named
Not just the palette — which colour is the button, which is a link, which is a background. A palette without roles gets applied differently by each person using it.
Button copy conventions
Sentence case or Title Case, first person or second, and the list of approved verbs. This is the most-clicked text in the email and the most inconsistently written.
The sign-off
Whether there is one, what it says, and whether it is signed by a person. Small, visible on every send, and the thing most likely to vary if unspecified.
Keep it to one page
A guide nobody reads changes nothing, and length is the main reason guides go unread. One page, referenced during drafting, beats twelve pages consulted once during onboarding.
The test is whether someone writing their first email for you can produce something that sounds right by reading it for five minutes. If it needs more than that, it is a brand book rather than a working document, and it needs a one-page summary in front of it.
What a guide does not fix
Consistency is not the same as quality. A guide makes every send sound like the same sender; it does not make any of them worth reading, and a rigidly applied guide can flatten the writing of someone who was doing something better.
Treat it as a floor rather than a ceiling: the standard below which nothing ships, with room above it. The alternative — enforcing it as a ceiling — produces email that is consistent and forgettable, which is a worse outcome than mild inconsistency.
Does the guide answer these?
- What the from name is, exactly, on every send
- Whether we say I or we
- Whether we use contractions
- Sentence case or Title Case in subject lines
- The exact type sizes, and the minimum
- Which colour is a button and which is a link
- The approved button verbs
- Whether emails are signed, and by whom
Frequently asked questions
Who should own the email guide?
Whoever writes most of the email, with sign-off from whoever owns the brand. Ownership by a brand team that does not send email produces a document about logos.
How often should it be revised?
When something in it is being ignored. A rule that everyone breaks is either wrong or badly explained, and both are reasons to revisit it rather than to enforce it harder.
Does the from name really matter that much?
It is the first thing a reader sees and the thing recognition attaches to. Changing it is one of the few design decisions that can measurably affect open rate and placement at the same time, so it is worth deciding once and leaving alone.