Hey all. I've heard that you can claim more for a business-related trip if you have taken passengers in your car. Is there a way of entering this on my mileage page?

Hello there, @Davesquick1s.

You'll need to add the vehicles first so you can add up quickly the business-related mileage. This way, you can keep track of your trips and vehicle info during the year, so you have everything you need to make deductions at tax time. 

Here's how to add many vehicles:

On a web browser.

1. Go to the Mileage or Trips menu.
2. Click the Vehicle icon.
3. Choose Add vehicle.
4. Enter the make and model, ownership status, and other info.
5. Hit Save.

On an iPhone or iPad (iOS).

1. Open the QuickBooks mobile app.
2. Click the menu ☰ icon and then Mileage.
3. Select Auto-tracking.
4. Hit Manage Vehicles.
5. Click Add new vehicle.
6. Enter the make, model, and ownership status.
7. Choose Optional info and fill out the remaining fields.
8. Select Save.

On an Android phone or tablet(iOS).

1. Open the QuickBooks mobile app.
2. Click the vertical ellipsis ⋮ icon and then Settings.
3. Choose Manage Vehicles.
4. Select Add new vehicle.
5. Enter the make, model, and ownership status.
6. Select Optional info and fill out the remaining fields.
7. Hit Save.

See his articles for more details: Set up mileage tracking and vehicles in QuickBooks Online and QuickBooks Self-Employed

Once you're already set up, you can now track mileage into QuickBooks. Just follow the steps in this article: Automatically track your mileage.

Also, you can check the HMRC website for the current flat-rate deduction amounts and examples.

If there's anything else you need help with, please let me know. I'm always here to answer it for you. Have a great day!