Use this document to add a line of service to an existing account through My T-Mobile.

1. From a computer, log in to My T-Mobile.
2. From the top of the page, click Shop, then click Add a phone/line.   
3. You may receive the following message when attempting to add-a-line:
   • Because of the nature of your T-Mobile account, you are unable to add a line. To make changes, or if you have questions, please call Customer Care at 1-800-T-MOBILE or visit a T-Mobile Retail Store.
4. Select GSM/Voice lines, Mobile Broadband lines, or both on the ADD A LINE screen.
   • You only see tabs for the product types you are eligible to add.
5. If the account is eligible to add lines, select the number of lines to add by product type and then click the Next button.
   • If you have to pay a deposit, the information also appears at this time.
6. When a screen appears to confirm the next step, click Continue.
   • This screen appears after almost every step to guide you through the AAL transaction.
   • You have the option to view/edit cart for the line you are working on to re-show the guided step screen.
7. After the eligible plans display, select your plan by clicking Add to cart.
   • If you decide to pool your lines (YES radio button), eligible Family plans display. 
   • If you decide to add an additional non-pooled line (NO radio button), eligible Individual plans display.
   • You may have the option to select between different individual plan types via a radio button.
   • A migration fee may display. 
   • Mobile Broadband plans only display if you opted to add a Mobile Broadband line. You may have the option to select between different mobile broadband plan types via a radio button and a migration fee may display.
8. Select a phone/device to purchase for this new line of service and click the Add to cart button.
   • Phones only display for GSM/Voice lines and Internet Devices only display for Mobile Broadband lines.
9. Select new services to add to this line.
10. When completed, click Done adding services to move to the next step or click Done adding services to skip this step.
    • If data is required for the device, you need to select your data access level by a radio button.
    • If data is not required, you may select no data.
11. Select accessories to add to this line.
12. When completed, click Done adding accessories to move to the next step or click Done adding accessories to skip this step.
13. If adding more than ONE line to a multi-line account, repeat the above steps for each additional line.
    • After each line is completed, a screen appears confirming the selections.
14. Click Next to display the Cart page.
    • The Review your cart page appears which provides the details of the rate plan, device, service, and accessories selected.
    • Any migration fees or deposits will display on the cart page.
15. Review the order, then click Check out.
    • The Customer information page displays.
16. Perform the following final actions:
    • Enter and verify the shipping and billing address details.
    • Select a shipping option.
    • Follow the on-screen steps to complete a port of a current number from another carrier, if desired.
17. Click Continue to Pay and Review.