Somebody on your team sent a customer three questions in one paragraph last week. The customer answered the first one, missed the other two, and now there's a second round of email that didn't need to happen. Nothing in that message was badly written. It was badly shaped, and shape is what formatting actually is.
The five parts of an email format
Almost every business email is built from the same five parts, in the same order. That structure is most of what people mean when they say an email is well formatted.
- Subject line. Specific enough to tell the reader what this is before they open it.
- Greeting. Their name, spelled right, at the formality the relationship calls for.
- Opening line. Why you're writing, in the first sentence.
- Body. One idea per paragraph, with the ask visible without scrolling.
- Closing and signature. A specific next step, then a sign-off and who you are.
What each part is doing, and where each one usually goes wrong:
| Part | What it's for | What good looks like | The common mistake |
|---|---|---|---|
| Subject line | Telling the reader what this is before they open it | Specific and concrete: "Invoice 4021: wrong VAT rate" | "Quick question", "Following up", or nothing |
| Greeting | Setting the register and confirming you know who you're writing to | Their name, spelled right, at the level of formality the relationship has | "To Whom It May Concern" on a message you could have addressed |
| Opening line | Saying why this email exists | The reason, in the first sentence | Two sentences of pleasantries before the point |
| Body | The actual content, in a shape someone can act on | One idea per paragraph, the ask visible without scrolling | A single block of text carrying four separate requests |
| Closing and signature | Saying what happens next and who you are | A specific next step, then a sign-off and your details | "Let me know your thoughts" and a signature with a quote in it |
Two things in that table are load-bearing and the rest is taste. The first is that the reason for the email appears in the first sentence. The second is that the ask is separable from the context: if someone has to re-read your message to work out what you want from them, the format failed, whatever the font was doing.
Everything else has more latitude than the internet suggests. "Hi Sam" is fine in most business contexts. So is a one-line email with no greeting at all if you're eleven messages into a thread.
The subject line does more work than the other four parts put together, because it's the only one that has to perform before the message is open. Make it specific enough that the reader could find it again in six weeks by searching for a word they'd actually remember. If you're writing to customers rather than colleagues, we've got 18 complete customer service emails, subject lines included, which covers the lifecycle cases in more depth than this page does.
How formal should it be?
Formality isn't a dial from cold to warm. It changes specific, structural things about the message, and it's worth knowing which ones, because most people either overshoot into stiffness or ignore the question entirely.
Going up in register changes four things:
- The greeting form. "Dear Ms. Okafor" is a different act from "Hi Sam". Use the full form when you've never met, when you're writing to someone in a formal role on a formal matter (a legal notice, a complaint escalation, a job application), or when you're the one asking for something.
- Contractions. Formal registers drop them. "I do not have a fix date yet" reads more distant than "I don't have a fix date yet". That's the whole effect, and it cuts both ways.
- Paragraph count and length. Formal email tends toward fuller sentences and more context before the ask. Informal email puts the ask first.
- The sign-off. "Sincerely" and "Yours sincerely" sit at the top, "Best regards" and "Kind regards" in the middle, "Thanks" and "Cheers" at the bottom.
Two conventions are worth knowing because they're the ones people get quietly wrong. In British usage, the sign-off depends on whether you named the recipient: "Yours sincerely" goes with "Dear Ms. Okafor", and "Yours faithfully" goes with "Dear Sir or Madam". American business usage mostly collapses both into "Sincerely" and doesn't make the distinction. The other is punctuation after the greeting: a comma is standard everywhere, and a colon ("Dear Ms. Okafor:") reads as formal American business correspondence. Nobody will hold either against you, but if you're writing to an institution that cares, these are the details it notices.
A formal subject line is the plainest one you'll ever write. No hook, no shorthand, just the matter and any reference number: "Invoice 4021: request for a corrected VAT rate". Save the personality for messages where personality helps.
Register is one question and word choice is another. Once you've settled how formal the message is, how to talk to customers covers the layer underneath it: which nouns to use, when to say "I" instead of "we", and how to refuse something without buying a second round of email.
Put together, a formal message is short and unornamented:
Subject: Invoice 4021: request for a corrected VAT rate
Dear Ms. Okafor,
I'm writing about invoice 4021, issued on 3 September, which applies VAT at 20% rather than the 5% rate agreed in our contract of 14 April.
Could you issue a corrected invoice before the end of the month? I've attached the original and the relevant section of the agreement.
Thank you for your help.
Yours sincerely, Priya Raman
Note what's doing the work: the reference number in the subject, the reason in the first sentence, and the ask on its own line. The formality is in the greeting and the sign-off. Strip those two and the same message works for a supplier you email every week.
Here's the part nobody says out loud: most business email now lives in the middle, and full formality in a support thread reads as distance rather than respect. If a customer writes "hey, this is still broken" and you answer with "Dear Sir or Madam, I am writing in reference to your recent correspondence", you've told them they're talking to a process instead of a person. Match the register they opened with, then move it up a notch, not four.
The exceptions where you should go formal and stay there: anything that might end up in a legal file, anything going to someone senior at a company you don't work with, first contact with a regulator or an institution, and anything where your reader's culture expects it and you can't tell yet.
How to format a reply
This is where most guides stop, and it's where the daily volume actually is. You send a handful of first messages a week. You send replies all day.
Do you greet again?
On the first reply, yes, briefly. By the fourth message in a live thread, a greeting starts to read like you've forgotten the conversation is ongoing. Drop it and open with the substance. The exception is a thread that's been dormant for weeks, where a short greeting signals you're picking it back up on purpose.
Where your text goes relative to the quote
The three layouts have names, and knowing them makes the choice deliberate instead of accidental. Wikipedia's article on posting style defines them cleanly: in top-posting "the original message is included verbatim, with the reply above it"; in bottom-posting "the reply is appended to a full or partial copy of the original message"; in interleaved posting "the original message is broken into two or more sections, each followed by a specific reply or comment".
| Layout | When it works | What it costs the next reader |
|---|---|---|
| Top-posting | Short replies, threads where everyone has the context already | The history piles up underneath, unread and unmanaged |
| Bottom-posting | Rare in business email now, reads as unusual to most recipients | They have to scroll past the quote to find your answer |
| Interleaved | Answering several distinct questions in one message | Nothing, if you trim; it's the clearest option for multi-question replies |
Almost everyone top-posts without ever choosing to, and there's a mechanical reason. The same article notes that mail readers including Outlook and Gmail insert a copy of the original into the reply and put the cursor above it by default. You top-post because that's where the cursor was.
The habit worth building is the one nobody has: trim the quote. The same article puts the convention plainly: quoted material "should be trimmed or summarized as much as possible, keeping only the parts that are necessary to make the readers understand the replies". In practice that means deleting the signature blocks, the legal footers, and the six earlier rounds nobody's going to read, and keeping the two lines you're actually responding to.
Here's the difference in practice. A customer writes in with three questions. The default reply looks like this:
Yes, that should be fine. Let me know if you need anything else.
Priya
On 12 September, Sam Webb wrote: Hi, a few things before we renew. Can we add two more seats mid-term? Does the export include attachments? And is the January invoice going to the new billing address? Thanks, Sam Sam Webb | Operations | Northgate Ltd | 0161 496 0112 This email and any attachments are confidential and intended solely for the addressee...
"Yes, that should be fine" answers one of three questions and Sam can't tell which. The trimmed, interleaved version:
Can we add two more seats mid-term?
Yes. I've added them today and they're active now; the extra cost is prorated to your renewal date.
Does the export include attachments?
It doesn't. The export covers message bodies only, so I'd hang on to the originals.
And is the January invoice going to the new billing address?
Not yet, it's still set to the old one. I've changed it now, so January onward will be correct.
Priya
It's longer to write and much shorter to read, and it ends the thread instead of extending it. That's the whole case for trimming.
Reply, or reply all
Microsoft's own guidance on replying and forwarding is more direct than most etiquette advice: "Before you select Reply All, consider whether everyone needs to see your reply, especially if the message was sent to a lot of people or distribution lists." The same page confirms a thing people get wrong constantly: attachments aren't included when you reply, only when you forward. If someone needs the file again, forward or re-attach it.
You can also change which button is the default. In Outlook on the web that's Settings, Mail, Compose and reply, where Reply means "Your reply is sent only to the sender" and Reply all means "Your reply is sent to everyone on the To and Cc lines". If your team keeps accidentally replying to forty people, that setting is the fix, not a reminder email. Getting people off a chain they don't belong on is a recipient-field problem more than a formatting one, and we cover the mechanics of that in showing and using BCC in Outlook.
When to start a new thread instead
Reply when it's the same question. Start fresh when the topic has genuinely changed, because a thread titled "Invoice 4021" that's secretly about next quarter's renewal is unfindable for everyone later. If you're pasting a saved block of text into a conversation that already exists, that's a slightly different discipline, and we've written up where that saved text should live and how to keep it from sounding canned.
What Gmail and Outlook do to your formatting
Here's the layer that page-one advice skips entirely. Your formatting isn't only what you typed. It's what your mail app was already set to do, on the way out and on the way in, and some of those defaults are working against you.
HTML, plain text, and the legacy one
Microsoft documents three formats, and the message format page is clear about what each costs you. HTML is the default in both new and classic Outlook, and it's the right answer for almost everything. Plain text "works for all email programs, but it doesn't support bold or italic text, colored fonts, or other text formatting", so your bullet lists arrive as dashes and your bold emphasis arrives as nothing. Worth knowing that this isn't strictly either/or under the hood: a message can carry an HTML version and a plain-text version together and let the receiving app pick.
Rich Text Format is the one to skip, and Microsoft is blunt about why. RTF "is a Microsoft format that's supported only by these email applications: Microsoft Exchange Client versions 4.0 and 5.0" and classic Outlook. Microsoft calls it "a legacy format" and recommends HTML instead. Nothing catastrophic happens if you send it, since Outlook converts it to HTML on the way out of your organization and the formatting and attachments survive, but you're choosing a format with a conversion step and no benefit.
To change it for one message in new Outlook: Options, then Switch to plain text. In classic Outlook: the Format Text tab. To change the default in new Outlook: Settings, Mail, Compose and reply, Message format. In classic: File, Options, Mail, "Compose messages in this format".
The setting that eats line breaks on the way in
This one catches people out because it works in the opposite direction from what you'd assume. If plain-text mail lands in your Outlook looking like a wall, that's usually your own Outlook reformatting it as it displays, not the sender writing it that way. Microsoft's KB 287816 documents the behavior: "By default, the Auto Remove Line Breaks feature in Outlook is enabled. This causes the line breaks to be removed. Any two or more successive line breaks are not removed."
Two things follow. Double line breaks survive, so paragraph spacing is safe and it's single breaks inside a block that disappear, which is why plain-text tables and addresses collapse. And you can turn it off on your own copy: File, Options, Mail, and in the Message format section clear Remove extra line breaks in plain text messages. Outlook isn't doing this behind your back either; the KB's subject is post items in a folder, where nothing tells you it happened, and it notes that email messages do show an information bar when line breaks are removed.
The practical upshot for a sender is the reverse of the setting: you can't control the reader's copy, so don't rely on single line breaks to carry meaning in a plain-text message. Use a blank line between blocks.
Gmail's two settings worth knowing
Gmail has a per-message plain text switch and a global default. Gmail's formatting page puts plain text mode under Compose, then More options, then Plain text mode. The global one is Settings, See all settings, then the "Default text style" section, then Save Changes.
That second setting is the one that matters for teams. It's set once per person, it applies to everything they write, and it's the reason half your colleagues are sending mail in a font nobody chose.
On mobile the picture thins out. The Android tab of the same page documents bold, italic, underline, text color, background color, unordered list, font and clear formatting. It doesn't document a plain text mode or a default text style. That's not proof the option is impossible to reach, but if you're writing your team's standard, don't assume phone composers can apply it.
Formatting that survives a phone and a screen reader
Advice in this area is usually vibes. One part of it is specified down to the decimal, and it's the part people get wrong.
Contrast is a number, not a matter of taste. WCAG 2.2's contrast minimum requires a ratio of at least 4.5:1 for normal text and at least 3:1 for large text, where large is defined as "at least 18 point or 14 point bold". Light gray body text on white, which reads as tasteful and minimal in the compose window, frequently fails that. If you've set a custom default text style in a pale gray, you've made your mail harder to read for everyone and unreadable for some people.
The rest is judgment, starting with this: don't put meaning in color alone. "The items in red are urgent" stops working for a colorblind reader, a screen reader, and anyone whose app strips your styling. Say "urgent" in the words.
Beyond that, a short list that holds up:
- Alt text on any image that carries information. If the image is decorative, it doesn't belong in a business email anyway.
- One column. Anything that looks like a layout will reflow unpredictably on a phone.
- Short paragraphs, because a phone screen turns four lines into twelve. Not because of attention spans.
- Lists for anything sequential or parallel. Prose is for argument, lists are for items.
You don't need a font-size rule with a fake number attached. Use your client's default size unless you've got a reason, and check the contrast if you've changed the color.
Formatting rules for a shared address
Everything above assumes one person writing from their own mailbox. If you run a support address, a sales address, or any inbox several people answer from, formatting stops being personal preference and becomes a house standard, and the failure mode is specific: five people each carrying their own default font, their own greeting, and their own sign-off make one company look like five freelancers who've never met.
Six decisions worth making once and writing down:
- The greeting. Pick a default form and when it changes. Most teams land on first name, with a fallback for when you only have an email address.
- Whether you sign with a personal name. Both work. "Thanks, Priya" builds a relationship and creates an expectation that Priya handles the next reply. "The support team" is honest about the queue and colder. Pick deliberately and be consistent, because switching between them inside one thread is the confusing option. This is where a format standard starts shading into a voice standard, and the voice half is covered in the customer service email templates.
- What the signature says, and what everyone's default text style is set to. Agree the fields and the order, then pick one font and one size and actually go and set them. A widely supported face like Arial, Helvetica, Georgia, Times New Roman or Verdana will render the same way for nearly everyone; the novelty font someone chose in 2019 will not.
- Plain text or HTML, and whether anyone's allowed to send Rich Text (they're not).
- Quoting and trimming. Whether people trim the thread on reply, and whether internal notes ever get quoted back to a customer. That second one is how a customer ends up reading "this account is always a nightmare, can someone else take it" in their own inbox, so it's worth a rule rather than an instinct.
- Who owns the standard. A formatting agreement nobody maintains lasts about a quarter.
The hard part isn't agreeing on these. It's that you can't enforce a house format from inside five separate personal mailboxes, and nobody can see what anyone else is sending. A shared inbox tool like TriageFlow puts the whole queue in one place, so replies are visible to the team rather than sitting in one person's Sent Items where the standard quietly drifts. If you're working out whether a shared address needs real tooling yet, the shared inbox guide covers the thresholds.
The formatting mistakes that actually cost you a reply
Ranked by how much damage they do, not by how often they're complained about.
- A vague subject line. It costs you opens, it costs you findability later, and it's the cheapest thing on this list to fix.
- Burying the ask. If the request is in the fourth paragraph, expect to send a follow-up. Put it near the top, on its own line.
- Multiple unrelated requests in one email. Reply rates drop to whichever one the reader felt like answering. Send two emails.
- A wall of text. No paragraph breaks, no list, no visual entry point. People triage their inbox by glance, and a wall loses.
- Pale gray body text below the contrast minimum, which is the mistake that looks like good taste.
- An untrimmed quote dragging six rounds of history and three signature blocks behind a one-line answer.
- A signature with a quote, a logo, and four social icons, which is noise on every message you'll ever send.
Notice what isn't on the list: your font choice, as long as it's legible and a normal size, and whether you wrote "Best regards" or "Kind regards". Those get the most discussion and change the least. The mistakes that genuinely need fixing after the fact are the ones in the To line or the numbers, and those turn into a race against your undo send window.
Frequently asked questions
How do you properly format an email?
Subject line, greeting, opening line that says why you're writing, body with one idea per paragraph, then a closing with a specific next step and your signature. That order is conventional enough that readers expect it, and the two parts that actually decide whether you get a reply are the subject line and how quickly the ask becomes visible.
What is the correct format for an email?
There's one conventional order: subject line, greeting, opening line that states your reason, body, then a closing with the next step and your signature. Inside that order there's more latitude than most guides admit. The two parts that genuinely matter are that your reason appears in the first sentence and that the ask is separable from the context; greeting warmth, sign-off wording and font choice are convention rather than correctness.
Does every email need a greeting?
A first message does. A reply four messages deep into an active thread doesn't, and adding one starts to read like you've lost the thread. The case where it's worth putting back: a conversation that's been quiet for a few weeks, where a short greeting makes it clear you're deliberately reopening it.
How long should a professional email be?
Think in structure rather than word count. One subject, the ask visible without scrolling, and one idea per paragraph will keep almost any email the right length on its own. If you can't get there, it's usually because the message is carrying two unrelated requests and wants to be two emails.
Should you quote the whole original message when you reply?
No. Keep the parts you're responding to and cut the rest, including the signature blocks and the older rounds. Trimming is standard practice in the posting-style conventions, and it's the single biggest improvement available to a reply, especially if you're answering several questions and can put each answer under its question.
When is it appropriate to use Reply All?
When everyone on the thread needs the information, which is less often than the button's position suggests. Microsoft's own advice is to consider whether everyone needs to see your reply before you select it, particularly on messages sent to large groups or distribution lists. If your team gets this wrong regularly, change the default reply button in settings rather than asking people to be careful.
How do I change the default font in Gmail or Outlook?
In Gmail, that's Settings, See all settings, then the "Default text style" section, then Save Changes. In classic Outlook, the compose format and font live under File, Options, Mail. Both are per-account settings, so on a shared address everyone has to change their own, which is the part teams usually discover after the fact.