Chris, diagnosed 1978

Contact Us

We offer a variety of ways to get the help you need, on your schedule, including 24/7 technical support.


Support Center

Did you know that Tandem has an extensive library of educational and self-help materials to help you get the most out of your Tandem pump?



Need help with your Dexcom CGM?

For Dexcom continuous glucose monitoring (CGM) specific issues including calibration prompt will not clear, sensor failure during the 2-hour warmup, “no restarts” alert or physical problems with your sensor or transmitter, such as bleeding, bruising, skin reaction, adhesive issues, applicator issues, or broken wires, please contact Dexcom using one of the options at or report the issue online at Please see table for a full list of who to contact for Dexcom CGM issues.

Tandem handles issues such as loss of connection (on pump only) and the invalid transmitter (Alert 29) on pump only.


Product Contact

Dexcom CGM Applicator

Common Issues: Physical Damage (e.g., Broken Needle, Cannula or Needle Retraction Issues, etc.), Deployment Issue, or Painful Insertion


Dexcom CGM Transmitter

Common Issues: Pairing Failure on Dexcom Mobile App, Unintended once per day calibration mode, Physical Damage, Transmitter Latch Issues, Difficulty Inserting or Removing Transmitter, Low Transmitter Battery Alert, Transmitter Failed Error, Overheating, or Shocking


Dexcom CGM Sensor

Common Issues: Physical Damage (e.g., Broken, Detached, Missing Sensor Wire, etc.), No Initial Calibration, Sensor Failure During 2hr Warmup, or New Sensor Inserted but Displays “No Restarts” (Alert 25), Inaccurate CGM Values, Calibration Prompt Will Not Clear, Early Sensor Expiration, Sensor Failure After 2hr Warmup, Pump Displays "---" or “Wait up to 3hrs”, Dexcom Mobile App Displays “Sensor Error”, Calibration Errors


Tandem t:slim X2 Insulin Pump with Dexcom CGM

Invalid Transmitter ID (Alert 29) on pump only, Loss of connection on pump only

If the Dexcom app is also not receiving data, Dexcom will handle the issues above.




Get in Touch

Technical Support

(877) 801-6901
24 hours/day
7 days a week

Pump Renewals

(858) 935-8951
Email Renewals Team
6:00 AM to 5:00 PM  (Pacific)
Monday - Friday

Order Support

(877) 801-6901
6:00 AM to 5:00 PM (Pacific)
Monday - Friday

Corporate Offices


11075 Roselle Street
San Diego, California 92121
(858) 366-6900
8:00 AM to 4:00 PM (Pacific)
Monday - Friday


1500 West Shoreline Drive
Boise, Idaho 83702
(858) 366-6900
8:00 AM to 4:00 PM (Mountain)
Monday - Friday



Send a Message

Are you already using Tandem products? If so, please call our 24-hour Technical Support Team at (877) 801-6901. For other inquiries, please complete our form below.

By submitting this form, you grant Tandem Diabetes Care, Inc. permission to add your contact information to our database to send you information and communications related to our products. We respect and uphold the confidentiality of your personal information, and will not share your information with any third-parties, except as noted in our privacy policy. A link to our privacy policy is available at the bottom of this page.