Competitor Sea-Land Service, which said its fuel costs have also soared, said it also will add a fuel surcharge but late this morning had not calculated how much.

Matson's fuel price has risen 32 percent over the last 12 months, said C. Bradley Mulholland, president and chief executive officer of the San Francisco-based subsidiary of Alexander & Baldwin Inc.

"We had hoped that the trend of rising prices would abate. However, as we approach 1997 and see no relief in sight, we find this fuel-related increase unavoidable," Mulholland said.

Matson put a 1.1 percent fuel charge into effect in June but refrained from adding it for the Guam-Micronesia service that began in February.

Sea-Land also had a fuel surcharge in June, of 1 percent. John L. Sutherland, Sea-Land vice president Hawaii-Guam, said today his company's fuel costs are 46 percent higher than they were in the last quarter of 1995.

Both companies said they can reduce or eliminate the surcharges when fuel costs go down again.

The lines said Hawaii consumer prices won't be significantly affected. Matson's example was the cost of shipping a car from Honolulu to Oakland. It was $798. The June increase added $9 and the December one will add another $5, said Jeff Hull, a Matson spokesman.

Sea-Land's Sutherland said the cost of shipping a 40-foot container of food from the mainland is about $3,000, depending on what's in it. A December increase of 6.5 tenths of a percent, such as the one Matson posted, would add about $19 to the freight charge for the whole container.