What You’ll Need
Before you start, keep these handy:- Your new Citi credit or debit card
- Your smartphone with an internet connection
- The last 4 digits of your SSN
- Your date of birth
- Your Citi Online User ID and Password (or be ready to enroll)
Step 1: Download the Citi Mobile® App
Head to your device’s app store and install the official Citi app:- iPhone users: Download from the App Store
- Android users: Download from Google Play
Step 2: Sign In or Enroll
Open the app and either:- Sign in with your existing Citi Online User ID and Password, or
- Tap Register / Enroll to create a new account using your card number and personal details.
Step 3: Open the Card Activation Menu
Once signed in:- Tap the menu icon (three lines) in the top corner.
- Select Card Services.
- Tap Activate Card.
Step 4: Enter Your Card Details
Type in the following exactly as they appear on your card:- 16-digit card number
- Expiration date
- 3-digit CVV (found on the back of the card)
Step 5: Confirm and Activate
Tap Activate. Within seconds, you’ll see an in-app confirmation message that your card is now active and ready to use.That’s it! Your Citi credit card is now activated and ready for in-store, online, and mobile wallet purchases.
Bonus: What to Do Right After Activation
Make the most of your new card by taking these quick actions:Add to Mobile Wallet
Add your card to Apple Pay, Google Pay, or Samsung Pay for contactless payments.
Enable Alerts
Turn on transaction and fraud alerts in the app for real-time notifications.
Set Up AutoPay
Never miss a payment by scheduling automatic monthly bill payments.
Create a PIN
Set up a PIN under Services → Manage PIN for ATM use and international travel.
Troubleshooting
App won't accept my card details
App won't accept my card details
Make sure you entered the card number, expiration date, and CVV correctly. Restart the app and try again.
I can't sign in to the Citi Mobile App
I can't sign in to the Citi Mobile App
Use the Forgot User ID / Password option on the sign-in screen, or call Citi at 1-800-950-5114.
Activation succeeded but card was declined
Activation succeeded but card was declined
Verify your billing address, check your available credit, and make sure the card is added to your mobile wallet correctly.