Is it normal that my new VISA debit card has almost the same number as the old one? Is it secure?
My bank issued me a new debit card (VISA Electron) because the old one expired and to my surprise, the card number is almost the same as on my old card. I don't think there would be much chance that this is a coincidence so is it a common practice that card companies somehow reserve numbers for their clients and then use them? (My old card has been issued in 2008, my new card in 2011.)
Is it secure to use a very similar card number?
I don't think the similarity in numbers would make it insecure. i'm pretty sure the code in the back changed
it is common to even get the exact same number. I get replacement cards all the time and all the changes is the expiration date and the number on the back. This is common between Visa and MasterCard but may vary depending on the bank or issuer.
Unluckily, this pretty dumb approach is common even in the case of _"100,000 card numbers were stolen"_ events. Which totally doesn't make sense when your compromised number was ...01 and now it is ...15 (where the last digits is the Luhn checksum, so it's really just 0 --> 1). Whoever stole the number can trivially add 24 months to the current date (to get the new validity) and change the last digit and recalculate the Luhn number to have a perfectly working combination again. I've complained with my bank about this twice, but of course to no avail, they simply don't care.
Almost the same -> they are different.
And there is some procedure on how those number are generated: the issuer has some code, the bank usually have some code, etc. You can take a look at this site.
If you ask two credit cards from the same issuer, same bank, you'll see that there are lots of numbers in common.
And even some cards have the same number, reissued, when they expire. So, you have received the same number again.