Because laws governing debit cards and credit cards are different, you should make this call first and within 48 hours of losing your wallet to protect yourself from fraudulent charges.  If you alert your financial institution within 48 hours, you maximum liability is $50; within 60 days, it is $500; after that, your liability is unlimited if someone is using your card.  Because your debit card is linked to your checking account, and your checking accounts may be linked to other accounts, expect to receive not only a new debit card / number but also new account numbers.  You will also need new paper checks. Keep in mind any automatic payments you may have through your debit card or checking account (phone bill, life insurance premium, etc.).  You will need to update the payment information on these when your account number changes. Yes, this is a hassle, but it is better than having your bank accounts drained and then having to jump through hoops to have your funds restored. You don’t actually need to cancel them, which would necessitate applying for cards all over again.  By reporting them as missing / stolen, you will get new cards with new numbers but be able to retain your current account status.  You maximum liability for fraudulent credit card charges is $50, and is $0 if you contact the company before the card is used fraudulently, but it is easier to prevent fraudulent purchases before they happen than work to erase them afterward.  Program the customer service numbers for your credit card companies (as well as your banks) in your phone so you can contact them quickly. Don’t forget store-issued credit cards as well. No, finding your lost wallet isn’t likely to be their first priority, but making a police report is an important way to protect yourself regardless.  Filing a report creates an official documentary record of the loss and your recovery efforts.  This can prove quite valuable for any insurance claims, fraud liability resolution, identity theft problems, or other issues that might arise....

TL;DR in Vietnamese:
Liên lạc với ngân hàng và thông báo mất thẻ ghi nợ. Thông báo mất thẻ tín dụng. Nộp đơn tường trình về việc ví tiền bị mất hoặc đánh cắp lên cơ quan công an. Gọi điện cho văn phòng tín dụng để bảo vệ điểm số tín dụng của bạn. Thay thẻ nhân dạng mới. Liệt kê những thứ có trong ví tiền.