---
title: Username and Email
description: "Follow this guide to understand the difference between **Usernames** and **Emails**, and how to access multiple username accounts that share one email. ## Overview **Username**: All usernames are unique. That means no two usernames can be the same. If an…"
url: "https://paiyroll.com/kb/username-and-email/"
updated: "2026-07-18"
category: Employees
---

# Username and Email

Follow this guide to understand the difference between **Usernames** and **Emails**, and how to access multiple username accounts that share one email.

## Overview

**Username**: All usernames are unique. That means no two usernames can be the same. If an employee works at two different companies, they will have 2 different usernames. The company creates the username.

**Email**: emails do not have to be unique, meaning there may be more than one username with the same email.

The usual scenario is to use the **same username and email.** This makes it very easy for the employee, as there's no confusion between usernames and emails.

## Examples

### Same Username and Email

Most employees will have one username which is also their email. This is the simplest and easiest to understand, for example:

| Username | Email |
| --- | --- |
| john.smith@gmail.com | john.smith@gmail.com |

### Multiple Usernames and multiple emails

If an employee is employed by more than one company, then different emails can work well. For example, using a work email at one company and a personal email at another company:

| Username | Email |
| --- | --- |
| john.smith@acme.co.uk | john.smith@acme.co.uk |
| john.smith@gmail.com | john.smith@gmail.com |

### Multiple Usernames and one email

if an employee works for more than one company, but only has one email, then each company must use a unique or different username.

Usernames do not need to follow the same format as emails.

The email will be the same, for example:

| Username | Email |
| --- | --- |
| john_smith@acme.co.uk | john.smith@gmail.com |
| john.smith_universal | john.smith@gmail.com |

## Login uses **Username**

Users always log in with their username, not email. This allows an employee to log in to any number of different company accounts.

If you are unsure which username, has been created for you contact your company paiyroll® administrator.

![](https://paiyroll.com/wp-content/uploads/2024/06/image-39.png)

## Errors

| Error | Action |
| --- | --- |
| User with this Username already exists | This means that the employee is/was was employed by a different client on our system. As described above, you will need to create a **unique** username which differs from the email, and make it clear to the employee that their username is different from their email. |