One Email Signature for All Google Workspace Users

The direct answer: a shared footer or a personal signature

Google Workspace offers two native routes, and they solve different problems. The Append footer is an admin setting. It adds the same text to outgoing messages for everyone in an organisational unit (OU), and people do not see it while they write. Users cannot change or remove it. A personal signature lives in each person's Gmail settings and can carry their own name, title and phone number. The Admin console has no field that fills those in person by person, so the personal route depends on each person typing their own details or on a script.

Legal details are the one part with a fixed rule. In the UK, section 82 of the Companies Act 2006 requires a limited company's business letters and order forms to show certain details, and the duty covers electronic documents as well as paper. Sources disagree on which regulations carry the detail: some cite the Companies (Trading Disclosures) Regulations 2008, others the Names and Trading Disclosures Regulations 2015. Check the current text on legislation.gov.uk before you write the wording. The details are the registered name, the part of the UK where the company is registered, the registration number and the registered office address. A link to these details is not enough; they must be shown in the text itself. Other countries set their own rules, so the UK is used here as the worked example.

The table below sets the three native and API routes side by side.

How the footer is set up, step by step

Start with the content. Write the footer as plain text with light formatting, because the footer editor does not accept HTML. Keep it to the legal lines and one standard contact line, so it reads cleanly under every message. Then work through the admin steps below.

1. Sign in to admin.google.com with an account that holds the Gmail Settings administrator privilege. A super admin has it by default.
2. Go to Menu, then Apps, then Google Workspace, then Gmail, then Compliance.
3. On the left, select the top organisational unit if the footer is for everyone, or a child unit if it is for one team. Child units inherit settings from the parent.
4. Scroll to the Append footer setting and click Configure, or Add another rule if a rule already exists.
5. Enter a description and the footer text. The limit is 10,000 characters, including any image. Use the formatting tools. Images must sit at a public web address; images stored in Google Drive cannot be used.
6. Decide whether the footer should also appear on internal messages, and tick the box if it should.
7. Save, then wait. Google says changes can take up to 24 hours to apply, so do not leave an update until the last day.

Before you roll the footer out, send a test message from an account inside the unit and from one outside it. Check the text, the line breaks and the image, and open the message on a phone.

Worked example: 40 staff in three units

Take a fictional company, Northwind Trading Ltd, a UK limited company with 40 staff in three units: Head Office, Sales and Finance. The top-level rule holds the legal lines: the company name, the place of registration, the registration number and the registered office address. Suppose that block comes to about 250 characters. Against the 10,000-character limit set by Google's admin help, that is 2.5 per cent of the space, which leaves room for a short notice if the lawyer asks for one.

Sales then wants a promotional line for its own staff. Create a second rule on the Sales unit only. Because child units inherit the parent's settings, Sales staff will receive the top-level block as well as the new line. Confirm the result in a Sales test account before you publish. Do not assume how two rules will look together until you have seen one real message.

The personal layer is separate. Each of the 40 people types their own name, title and direct line into Gmail settings. Their outgoing mail then carries the personal block first and the company footer below it. On a reply, the footer sits at the bottom of the whole thread, under the quoted text, not under the sender. That is the trade-off of this design, and it is the reason many teams with a strict brand move to a script at this size. Forty people typing their own layouts means forty versions.

Cases that change the answer

Automatic name and title on every email. If the business needs each person's name, title and phone number to appear without their action, the Append footer cannot do it. The usual options are a script that calls the Gmail API or a signature manager app from the Google Workspace Marketplace. The API's sendAs settings accept a signature for each address. For addresses other than the primary one, only a service account with domain-wide delegated authority can update the signature.

Aliases and second addresses. The footer also applies to messages sent from Google Workspace aliases, so an alias inherits the footer of its unit. A personal signature, by contrast, is set per send-as address. A person who sends from a second address needs that address set up with its own signature.

Internal mail. By default the footer applies only to messages going to recipients outside the organisation. Tick the internal option if the wording must also appear on internal messages. Whether internal mail needs the legal lines is a question for your lawyer, not for the admin console.

Encrypted mail. The footer is not supported for messages encrypted with Client-side encryption for Gmail. Those messages will not carry it, so do not rely on the footer for them.

Caps and size. A footer can hold up to 10,000 characters. A personal signature in Gmail also allows up to 10,000 characters, and an image counts toward that limit. Google's guidance for footer images suggests 70 to 100 pixels high and 300 to 400 pixels wide, with a maximum of 100 by 1000 pixels.

Leavers and moves. The footer reaches the people inside a unit, so moving someone to another unit changes what they send. A departing employee's account is removed or suspended, and their personal signature goes with it. The steps for that handover belong in your HR and IT process.

Common mistakes

The most frequent gap is the double block. Staff keep their personal signature, the footer is added below it, and the company name and registration details appear twice in one email. Decide which block owns which content before you publish.

Setting the footer at the wrong level is another. Check the organisational unit on the left before you save. A footer set at the top level reaches every unit, and a rule set on a child unit reaches only that team.

Teams also paste formatted content from a document and expect the same layout. The footer editor does not accept HTML, so table layouts and custom code appear as plain text or break. Using an image from Google Drive fails for the same reason: the image needs a public web address.

Expecting an immediate change is another common error. Google's timing is up to 24 hours, so a footer change scheduled for the morning of a deadline may not be live in time.

The last mistake is treating the footer as a complete compliance answer. The footer carries the lines you choose. Whether a disclaimer, a confidentiality notice or a regulated sector line belongs in it is a decision for your lawyer.

What to check with HR or a lawyer

Ask a lawyer which company details your business must show, in which country, and whether any notice belongs on every email. For a UK limited company, the answer starts with section 82 of the Companies Act 2006, read together with the regulations that sit under it. The footer can place the wording, but it cannot decide what the law requires.

Ask HR who may carry a job title on a signature, and what happens to signatures when someone changes role or leaves. If a signature change touches a person's job title, pay or role, agree it with the employee first, and apply the notice and consultation rules that your country's employment law sets.

Check the data rules in your country before a script reads names, phone numbers or photos from the staff directory. Limit the fields the script reads to what the signature needs.

This explains the rule in general terms; it is not legal or tax advice for your case.

Many employers now hand routine HR and payroll paperwork to AI workers, such as collecting staff details from a directory, preparing onboarding documents, chasing missing forms and building monthly reports. A person still reviews each output before it reaches an employee or a regulator. The signature script described above follows the same pattern: the system performs the repetitive writing, and a named person checks the result.