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Activate a New Card
Step-by-step guides to activate credit, debit, and prepaid cards online, by phone, or through mobile apps.
Fix Activation Problems
Troubleshoot common activation errors with proven fixes — from browser issues to server outages.
Card Security Tips
Learn how to protect your card from fraud with alerts, 2FA, PIN best practices, and safer online habits.
Frequently Asked Questions
Quick answers to the most common questions about card activation, payments, and account management.
Popular Guides
Jump straight into our most-read step-by-step guides:Credit Card Activation
Activate your Citi credit card online in minutes.
Debit Card Activation
Activate your debit card at an ATM, online, or by phone.
Prepaid Card Activation
Get your prepaid card ready to use with quick mobile activation.
Gift Card Activation
Activate and register your gift card for online and in-store use.
Lost or Expired Card Help
What to do if your card is lost, stolen, expired, or won’t activate.
Need More Information?
Browse our complete library of activation walkthroughs, troubleshooting tips, and helpful articles — all designed to get you back on track quickly.
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