D.C. councilman John A. Wilson, chairman of the council's finance and revenue committee, declared yesterday that major tax increases -- probably the biggest in District history -- are inevitable in the fiscal year beginning next Oct. 1.

Predicting that "our misery index is going to go up awfully high in the next year," Wilson stated publicly what his council colleagues and other city officials have begun to recognize: that Mayor Marion Barry's pledge to balance next year's budget without a tax increase probably cannot be redeemed.

At a "round-table meeting" he called to discuss the revenue estimates Barry and his staff used in calculating next year's budget, Wilson threw astronomical figures around like confetti at a party. He said the amount of money that will have to raised could range from $215 million up to $400 million. Asked afterward if he was serious about the figures, he said, "Of course I'm serious. You think I'm not serious? You think I just go around saying stuff?"

Since Wilson's expressed intent was to persuade his colleagues that "We have to cut the bull -- either you raise the taxes or you cut all that stuff out of the budget that nobody wants to cut out -- " and since the impact of a tax increase of that magnitude on the community would be staggering, it is probable that the package eventually adopted will be much smaller.

Wilson claimed that Barry's attempt to avoid any tax increases next year is unrealistic. The mayor proposed to begin repaying the city's cumulative deficit with new borrowing from the federal treasury that would have to be authorized by Congress, to balance the 1982 budget by persuading Congress to reinstate the tax on the incomes of suburban professionals, and to withhold any pay increases for city workers next year unless Congress approves a major increase in the annual federal payment.

"It is essential to realize," Wilson said, "that there is not going to be any sizable assistance coming from outside of D.C. to deal with the problem. . . We can't count on any taxes that call for implementation by the Congress." He said it is certain that city workers, who are now bargaining with the city over this year's pay will get an increase next year, whether Congress puts up extra money for it or not. An increase of just 7 percent in their salaries, he said, would cost $45 million -- for which there is no money in Barry's current proposals.

With the tax increases on sales, commercial property and gasoline that went into effect last summer, tax rates in the city are among the highest between Richmond and Baltimore. Barry has argued that any further increases would put an unfair burden on city residents and would be counterproductive because they would discourage business investment here. His staff calculated last summer that if it were necessary toraise the $2.15 million, Barry wants to borrow this year through taxes, personal income taxes might have to be raised 20 percent and property taxes more than 40 precent.

Wilson, a Democrat who represents Ward 2, said it would be necessary to raise not only the $215 million but also whatever additional revenues would be needed to balance for real a 1982 budget that is now balanced only in theory. He said that in drafting a package of tax legislation, he is "trying desperately" to avoid raising property taxes and the personal income tax. Asked what that leaves besides the business taxes that are already the area's highest, he said, "there are plenty of other things you can do," but he declined to specify them.

Wilson's views are influential on the council, but not all of his colleagues share his zeal for the unpalatable. Councilman David Clark (D-Ward 1), for example, said he was "not given to supporting tax increases until we are satisfied some waste has been cut" -- especially in the public school system.