Charge holiday gifts now and receive a big surprise in January.

That "surprise" for card-holders carrying balances will be higher rates on their post-holiday credit card statements.The recent rate hike by the Federal Reserve started a domino effect that resulted in a 0.75 percent increase in the prime lending rate, which will soon be passed on to variable card rates tied to it.

Nearly three-fourths of all cards these days are variable, with adjustments quarterly or monthly. While all are affected by rising interest, the most expensive cards with rate spreads 9 percent to 12 percent over prime will undergo the most noticeable change.

For example, the General Motors card, which came out in the fall of 1992 at 16.4 percent, will be a whopping 18.9 percent in December, according to RAM Research Corp. The average nationwide card rate of 17.54 percent is headed for 18 percent.

"A lot of consumers who didn't even realize they had a variable-rate credit card are about to get a wakeup call in the form of higher card rates," said Robert McKinley, president of card-tracking RAM Research in Frederick, Md., who notes that even many fixed-rate cards, which adjust less frequently, will also be increased the beginning of next year.

Smart consumers spent the past year seeking out deals. Aggressive low-rate card issuers have seen business jump, with First USA's credit assets up 64 percent for the year, Signet Bank up 40 percent and Wachovia up 22 percent.

Running up heavy card debt during the holidays has never been a good idea, but this year it's worse than usual.

"We see a 25 percent increase in people coming into our offices for help in January and February because of the impact of holiday overspending on credit," said Durant Abernethy, president of the National Foundation for Consumer Credit, Silver Spring, Md., which has 1,103 counseling offices in North America.

Don't be wooed by easy payment plans. "I strongly advise that consumers avoid `skip-of-payment' options in which the card issuer gives you an opportunity to skip a payment this month," said Ruth Susswein, executive director of the Bankcard Holders of America, Salem, Va. "This offer only benefits the issuer, since you didn't reduce your balance at all that month and, in the end, the issuer will wind up with extra money from you."

Be careful. "Take only one credit card with you when you shop, so if you lose your purse or billfold, you won't have lost a pack of cards that will require notifying each issuer," said Robert Johnson, senior research associate with the Purdue University Credit Research Center.

Stick to your original plans. "Don't feel you have to spend a lot of money. Figure out how much you can afford, and enter the store with a concrete plan," said Marie Stevens, counselor with United Charities Consumer Credit Counseling in Chicago. "That way, you're much less likely to wander around the store, then buy something three times more than you can afford because you think it's nice."

Some advice on holiday shopping:

- First prepare a list of all holiday expenses, including gifts, travel and entertainment.

- Suggest new family traditions to help with expenses, such as drawing names for gifts or setting price limits.

- Ask yourself if, during the previous month, you were able to pay only the minimum on your credit cards, whether you used cash advances from one card to pay off another and whether you dipped into savings.

- Try to buy with cash. Shop for the best prices and don't buy on impulse.

- If you must use credit, use only cards or accounts with the lowest interest rates and most advantageous repayment plans.

- Don't leave credit cards, receipts or carbons where anyone can pick them up.

Should you run into credit problems, call Consumer Credit Counseling Services toll-free at 1-800-388-2227 to obtain the location of the counseling center nearest you.

For a list of the lowest cards, send $5 to the CardTrak newsletter at Box 1700, Frederick, MD 21702. The low-interest/no-fee card list of Bankcard Holders of America is available for $4 from that organization at 524 Branch Drive, Salem, VA 24153.