Howard County homeowners will pay an average of $70 more in property taxes next year under a 1984 budget tentatively approved early today by the County Council.

The higher tax rate was approved in a four-hour meeting after the five-member council trimmed $2 million from County Executive J. Hugh Nichols' $112.5 million spending proposal for the coming fiscal year.

Nichols had requested a 32-cent increase on the current tax rate, which, at $2.39 per $100 of assessed value, is one lowest of counties in the Baltimore-Washington corridor.

The council, however, voted in an informal work session to allow at most a 23-cent rate increase. The council cut $1.1 million from the school budget, which accounts for more than half of county spending, and made other cuts in police, public works and office budgets. Further cuts may be made today; the council's final budget vote is scheduled for Thursday.

A 22- or 23-cent increase in the tax rate will raise the annual tax bill roughly $70 on a $100,000 home next year, said Raymond S. Wacks, the county budget administrator. The average sales price of used and new houses in Howard is estimated at $100,000, county officials said. The current $1,084 tax on that average Howard County home would climb to $1,154 under the tentative budget, Wacks said.

Several council members said they would push for even deeper budget cuts today. "I don't think the people of Howard County would be happy with even a 15-cent increase on the rate," said council member James H. Clark, an Ellicott City Democrat.

Clark caused a furor among county workers last week when he proposed delaying or eliminating annual cost-of-living increases and merit raises for employes as a way of diminishing the expected tax increase.

About 150 of the county's 1,100 full-time employes jammed a budget hearing last Thursday to protest Clark's proposal, and dozens of uniformed firefighters and police officers turned out last night for the council deliberations. County employes now receive automatic 5 percent raises and cost-of-living increases.

Clark said such pay increases should be "earned, not automatic."

County employes, meanwhile, have sent petitions to council members demanding no changes in the two yearly raises. "We may not like a flat merit increase, either," said J. Edwin Riddle, who represents workers before the county personnel board. "But we didn't create it. So we have to live with it."

Many of the 400 county workers whose salaries are frozen at the top of the pay scale need the raises to keep up with inflation, Riddle added.