Maryland Gov. Harry Hughes, coming up against a self-imposed deadline for submitting plans to resolve the state's savings and loan crisis, said today that an unexpected $118 million budget surplus will help him ease the crisis and maintain current programs.

Hughes pledged flatly that no taxes will be increased next year.

The surplus, which was announced in a report today at the annual Board of Revenue Estimates meeting here, is about $70.8 million more than earlier estimated, and Hughes said he will reserve "at minimum" $50 million to pay off any losses resulting from resolving the savings and loan problem.

The state's liability in the crisis could be far greater than $50 million. The combined debt at the three largest thrifts under state control is now estimated to be as much as $300 million.

The state hopes to sell two of those thrifts, and is in the process of selling the assets of Old Court Savings and Loan of Baltimore to reduce its estimated debt of $175 million. Some of the losses could be covered through the $150 million insurance fund that the state took from the private insurance corporation that was dissolved after the crisis hit in May.

Hughes also said he is contemplating creation of another reserve fund recommended by a New York bond rating house to guard the state's coveted AAA bond rating.

Nevertheless, Hughes said, when he submits his fiscal 1987 budget to the General Assembly next month, the last of his eight-year tenure, he will maintain current programs as well as recommend pay raises for state employes and increases in welfare grants. He also reiterated his intention to submit a comprehensive "housing initiative" to enhance housing opportunities for low-income families.

While saying he could not estimate the total impact that the savings and loan crisis will have on next year's budget, Hughes said, "Whatever we might have to do to finally bring a resolution to this problem, we can do better with less pain if we have strong revenue estimates, as this report reflects."

Hughes has promised both the legislature and the rating agencies that evaluate the state's creditworthiness that he will have a plan available by the time the General Assembly convenes next month. Lawmakers, who have already tagged savings and loans as the top priority of the forthcoming budget, hailed the estimates at the meeting of the board, which is made up of the state's financial officers.

"It's good news, especially in light of the savings and loan crisis, because if we were facing this in a down year, we'd be in really bad shape," said state Sen. Laurence Levitan (D-Montgomery), chairman of the Budget and Taxation Committee, one of two legislative panels that reviews the governor's spending proposals.

State Comptroller Louis Goldstein said the additional $118.4 million comes mainly from higher than expected lottery revenues, real estate transfer tax money and "construction activity," combined with a $47.6 million unobligated fund balance at the close of the last fiscal year on June 30.

Lottery ticket sales, the state's third largest general fund revenue source after income and sales taxes, are expected to yield $250 million this fiscal year, almost $7 million more than originally budgeted. The lottery is expected to bring in more than $313 million in fiscal 1987, " . . . If we were having this in a down year, we'd be in really bad shape." -- Sen. Laurence Levitan which begins July 1. "It's amazing how people want to gamble," Goldstein said.

State Budget and Fiscal Planning Secretary H. Louis Stettler III said that estimates give Hughes close to $100 million in so-called discretionary funds above what is needed to pay for automatic inflationary growth in the budget, as well as pay raises and increases in welfare programs. According to several lawmakers, the latter increases are estimated at 4 and 5 percent, respectively. Overall Hughes would have about $4.5 billion in the fiscal 1987 general fund, an increase of about 8.4 percent over the current fiscal year, the board said in its report. And although officials estimate somewhat slower economic activity during the next 18 months, they noted that the state economy "continues to expand briskly," and unemployment, at 4.2 percent as of September, is at its lowest level since April 1974.

Hughes, who is expected to run for the U.S. Senate seat being vacated by Republican Sen. Charles McC. Mathias Jr., pointedly took note of the unemployment rate by saying, "Sometimes you hear the statement, not as frequently now as you used to, about the antibusiness climate in Maryland. There are no facts to justify that, no facts at all. The low unemployment rate is the best proof of that."

Other officials, noting that the state has far to go before resolving its most pressing fiscal dilemma, were more cautious in their optimism.

"I think you're probably talking close to $100 million that will be used for the S&Ls and a rainy day fund," Levitan said. "The problem is, if you're going to have a new program like a housing initiative, the question is, where are the dollars going to come from?"

But House Speaker Benjamin L. Cardin (D-Baltimore) said, "I think we'll have enough money. I think we can do it all." CAPTION: Picture, Gov. Harry Hughes . . . $118 million available; Chart, Maryland General Fund.