After 16 years, American Express and Costco are divorcing. Amex moved out June 19 and the old card held dear by some Costco members is now "dead to us." It can no longer be used at Costco or anywhere else after the 19th.

By now every Costco member should have received a new Costco Visa Anywhere card (see below if you haven't). Cardholders have to activate it before it can be used Monday, June 20. The new card may be used anywhere Visa is accepted. (By the way, any Visa card can now be used at Costco.) It provides better benefits than the dead card. Cardholders will now get 4% cash back on gas purchases up to $7,000 (old benefit was 3%). Restaurant and travel expenses will get 3%, Costco purchases 2% and everything else 1%.

What's interesting is that Bank of America is now offering 2% rewards for purchases at warehouse clubs such as Costco and Sam's Club. Credit card experts expect more Visa issuers to follow suit. "The smart Visa card issuers will ride the wave and pick up some low-hanging fruit by offering at least a temporary bump in rewards at the warehouse clubs," said credit card expert John Ulzheimer.

My colleague Paul Joppa offers this tip: "Chase Freedom is offering 5% for warehouse clubs for this quarter and next. I heard that they will be offering it in the fourth quarter too. It is too late to register for this quarter for those who didn't. Does not include gas, fuel, wholesale club specialty service purchases such as travel, insurance, cell phone and home improvement. The way around the gas part would be to get gift cards and use those to buy gas. Limit is the first $1,500 in purchases."

It's too soon to say if some MasterCard issuers will follow suit by offering a similar 2% reward at Sam's Club. Launched last year at Sam's, MasterCard offers 5% cash back on gas, 3% on dining and travel and 1% on everything else, including Sam's purchases.

Note: If you want to earn 2% on purchases at Sam's Club, you need the Plus membership for $100 a year. Members will then get a check at the end of the year from Sam's Club. Having Costco's standard $55 membership entitles Visa cardholders to 2% cash back, but Costco's Executive members get an additional 2% on top of that.

If you have not yet received from new Citi card from Costco, call 1-866-241-8684 or go to www.citi.com/welcomecostco. A telephone service rep said Sunday that Citi has had some issues with people not receiving their cards.

There is no need to cancel your now defunct American Express Costco card. It can be destroyed eventually although you may want to wait until you're sure there are no returns or other issues. Returns made from purchases made on the old Amex Costco cards will be handled on a case by case basis by the merchant.

Costco has six locations in the Twin Cities, one in Rochester and one in Baxter.