OF ONE THING you can be certain this theater season:

Prices are up.

So are expenses.

Four seasons ago the Theater Guild subscription offered twelve attractions at a price range from $70 to $126. Now the Guild offers ten productions from $88.50 to $141.75. Complaints about these prices and the Guilds unhelpful policy regarding ticket exchanges never have been sharper.

Having held the same scale for several spiraling years, Arena Stage has a modest rise for its eight-play series, last year's $22.90 to $53 going up to $27.70 and $68.50. This rise is less than those of comparable theaters elsewhere.

Miraculously, the Folger holds to its $18 to $26 scale, though openings, cast receptions included, are a flossy $40 for its five plays. With no mortgage or rent to pay, the Folger needs grants to support its Equity players in a minute auditorium of but 214 seats.

Those who don't think through the problem complain about subscriptions, wanting to see only what people are talking about. With such attractions as bait, the subscription plans make possible proudctions which quite probably never would get onto a stage. This season the Washington Performing Arts Society has worked out three different series from seventy concert events, with little known artists supported by the celebrated.

Reasons for price rises are obvious. Power costs alone have zoomed. A new Equity contract, retroactive to June 28, is adding appreciably to costs for touring. It takes $90,000 a week to keep Pippin , recently at the Opera House, alive. Costs for one big touring musical have just jumped from $114,000 weekly to $125,000.

Much is made of the fact that last season's theater grosses, according to Variety, set a new record, over $93 million on Broadway and over $82 million on the road, figures which do not include resident professional theaters.

Small wonder records were set. Prices were higher. It does remain cheaper to go to the theater here than in New York, where the top weekend scale hits $20 a ticket.

Despite the "record grosses," quality was not artistically outstanding. Even finding worthwhile touring productions for this season demands miracles.

For all the concern over prices, reflected in heavier letters and phonecalls than usual, the hand-tooled craft of theater long since has become an elite luxury. There's no way around that. After movies took a huge slice of theater's audience, TV moved in and made the admission price one's ability to endure commercials, the worst sin ever committed against a noble invention.

Economics are related to quality, though the former does not guarantee the latter. Whatever happened to the Washington Theater Club, the D. C. Black Rep, the American Theater, the West End and all those high hopes for Ford's? Even the hopefully named Toronto Free Theater charges admission.

Here are the more substantial theatrical plans for coming season: Kennedy Center

The season begins with two blockbusters. Catnip to an enormous public, Mary Martin is playing at the Eisenhower in Aleksei Arbuzov's Do You Turn Someraults? Costarring in this romatic comedy by the Soviet Union's most popular contemporary playwright is Anthony Qualye, who appeared in its London version, Old Times, opposite Peggy Ashcroft. The run is through the 24th (Kennedy Center details at 254-3600).

Starting with a benefit preview on the 14th at the Opera House, where it will remain through November 5, A Chorus Line is the decade's smash musical, a semi-documentary look-in on auditions for chorus spots in a musical. Micheal Bennett's choreography and direction is to a book by James Kirkwood and Nicholas Dante and a score by Marvin Hamlisch and Richard Kleban. Now into its third New York year, there are two other American companies and others in London and Sydney.Quite literally, profits from this keep Joseph Papp's New York Shakespeare Festival alive.

Next at the Eisenhower will be Arnold Wesker's The Merchant , the English writer's variation on The Merchant of Venice , playing September 29 through November 5. Zero Mostel stars in director John Dexter's cast, which also includes Sam Levene, Marian Seldes, Roberta Maxwell and John Clements.

Eugene O'Neill's A Touch of the Poet , starring Jason Robards and Kate Reid under Jose Quintero's direction, will play November 14-December 17.

With Jane Alexander as the first woman on the Supreme Court, a conservative, and Henry Fonda as one of its famed liberals, the new Lawrence and Lee play, First Monday in October will run December 23 through January 28 under Edwin Sherin's direction.

Before the annual American College Theather Festival April 10-22, the Eisenhower will have three other plays, though dates have yet to be settled: Preston James's A Place on the Magdalena Flats , Samuel Taylor's Gracious Living and Alan Ayckbourn's Bedroom Farce , with Peter Hall repeating his staging of the British National Theater original.

With opera and ballet dominating the Opera House after A Chorus Line , a new musical, Sunset Strip is expected January 2 for a five week run. Alexis Smith is the probable star and Tommy Tune will both choreograph and direct.

Another long-run Broadway musical, The Wiz will be along in the Opera House June 5-July 15.

Despite its leaky roof , the center's top floor is coming to life through its Musical Theater Lab's free performances and the new experimental theater, Japan's second gift to the center (It also gave the Opera House curtain), may be open by next summer.

Theater Guild subscription attractions for this season are Do You Turn Somersaults? A Chorus Line, The Merchant, A Touch of the Poet, First Monday in October and The Wiz , with four more shows will to be decided on. Arena Stage

In its Arena and Kreeger theaters, Arena Stage plans eight productions. It also will expand use of its Old Vat Room, where a series of In-the-Process works will be a second subscription series. Off subscription, Starting Here, Starting Now will play the Old Vat November 22-December 18. This Richard Maltby Jr. and David Shire revue will have its original Manhattan Theater Club trio performing in cabaret atmosphere. Arena also presents its youth-oriented, locally mobile Living Theater. Here is the series of eight major offerings; details at 554-7890:

The Kreeger opens first, with Elizabeth Swados' Nightclub Cantata , a unique musical mixing humor, poetry and sketches. Admired at New York's Top of the Gate last winter, this will have some new Swados material for Washington. Opening October 7 to run through November 20.

The National Health, Peter Nichols' satire on British socialized medicine in a hospital ward, opens the Arena, October 14-November 20.

The Caucasian Chalk Circle , John Holmstrom's adaptation of the Brecht drama which opened the present Arena Stage, its third home, in 1961, will return there December 2-January 8, a reminder that sixteen years is either very long ago or only yesterday.

Comedians, Trevor Griffiths' comedy drama about a school for fledgling comics in Manchester, England, occupies the Kreeger January 13-February 26. A New York failure, this is one of producer Zelda Fichandler's occasional "Second Chance" choices.

A Streetcar Names Desire , postponed from last season, will run in the Arena February 3-March 12.

Working , for the Kreeger March 10-April 23, will be a major event, a musical treatment of Studs Terkel's striking volume about Americans and their jobs. Stephen Schwartz, composer of Godspell, Pippin, The Magic Show and portions of Mass , is the composer, lyricist and director. Produced in assocation with Chicago's Goodman Theater, Working will open there in January and the Kreeger version may benefit from this novel tryout.

Hamlet , still uncast, will make its Arena Stage bow March 14-April 30. It will be followed by a new American play, still unchosen, May 5 through June 11. The National

Bubbling Brown Sugar pays a return visit to E Street, where it tried out before its New York run, September 13-October 9. Phone information at 628-3393.

For Colored Girls Who Have Considered Suicide/When the Rainbow Is Enuf, Joseph Papp's production fo the haunting melange of poetry and movement by Ntozake Shange, will run October 10-November 6.

Spotlight , a new musical to star Dan Dailey as a famous star whose children also take to performing, has music by Jerry Bressler, lyrics by Lyn Duddy and book by Richard Seff, tries out November 7-December 4.

James Earl Jones as Paul Robeson is a new monodrama scheduled December 5-31.

Two new musicals are penciled in for the National. The fisrt, adapted from Van Druten's Voice of the Turtle, is mentioned for January 2-28, while Ziggy , a revue in the manner of Ziefeld Follies to star Judith Hameson, is scheduled January 30-25.

A new touring company of Annie is scheduled for a ten-week run starting February 26.

(The Theater Guild also offers a series of four National productions, scaled from $29.75 to $56.75, but the exact choices still have to be announced.) Ford's

F.D.R. , a solo play by Dore Schary, who wrote Sunrise at Compobella about the same president, with Robert Vaughn as Roosevelt II, is to play October 4-22.

And Still I Rise, a new musical work by poet May Angelou on the black experience, with two principal players and a chorus of twelve, opens November 1 to stay through December 11. Information at 347-6260. Dinner Theaters

This category, while rarely art in the theatrical or cuslinary sense, is a developing area of theater, attracting audiences not generally theaters patrons and expanding talents in theater crafts. These are the top three:

Burn Brae, Burtonsville, was the local trend-setter and in its tenth year is the most spacious and popular. Long runs, indicate wide patronage. How to succeed in Business Without Really Trying continues through October 9, with the Rodgers and Hammerstein Carousel to follow on the 12th. Phone 384-5800.

Hayloft, Manassas, gives chef Georges Richa equal billing with its attractions. The current Las Vegas revue, Bottoms Up, ends a summer run the 18th, with TV's Virginia Graham to star in Any Wednesday September 20 to October 23. Mister Roberts will follow, October 25-November 27. Phone 591-8040. It's the area's sole Equity dinner Theater.

Harlequin, Rockville, has youthful, zesty atmosphere and unique appeal. When the current George M ends its run, the likely successor will be the 1927 version of Good News, bypasssing the recent, written-for-stars version. Phone 340-8515.

The above are the area's major theaters, but there are a dozen other categories, groups headed by paid staffs, those whose performers receive non-supportive allowances, special interest groups, university drama departments, school and church players, children's theater, puppet companies and "alternative theater," which, under very modest circumstances attempt voyages into uncharted seas, sometimes with not unimpressive results. Omitting many, here are some: New Playwriths

At 1742 Church St. NW the New Playwrights' Theater of Washington is the area's most creative since the rise of Arena Stage, dedicated to development of our theater's most pressing need, new scripts.Pinnacle, a story of htree days in a needle-point factory by Mark Stein, will begin Wednesday through Sunday performances October 5. Producing director Harry Bagdasian and artistiv director PaulHildebrand also forecast: Memories for an Anniversary, by Ernest Joselovitz, author of last season's Hagar's Children; War Games, a drama of children in Northern Ireland by Gerald MacDonough to be staged by Robert Graham Small; House of Bedlam, a study of Ezra Pound by Ken Arnold; two one-act plays by John Sedlak and Hildebrand and Eddie's Catchy Tunes, by Tim Grundmann.

Sunday afternoon readings and another Monday/Tuesday series are planned. Details at 232-1122. Robeson Center

With the collapse of the D.C. Black Rep, this spot at 1632 O St. NW is one of the remaining hopes for black theater. Another is Harry Poe's mobile Ebony Impromptu Company. Its simple quarters were the original name is far from simple: "The Paul Robeson International Center for the Performing Arts and Humanistic Study." Founder Jay Williams now is into his third season, a period when grants decision-makers begin to take a project seriously. Owen Dodson, former head of Howard University Theater, will stage Oedipus Rex late this month, when the Robeson's downtown Sandwich Soup Theater also hopes to begin operations in the onetime Peking Restaurant. Phone 232-2554. Back Alley

Also, accenting ethnic groups, the small basement theater at 1325 Kennedy St. NW, with its downtown Back Alley Studio at 617 F. St. NW, plans five major productions uptown starting next month with Hot I Baltimore to be followed by Tricks, introduced at the Workshop, The Wonderful Ice Cream Suit, Miguel Pinero's Midnight Moon at the Greasy Spoon and Martin Duberman's new Kerouac. Phone 638-2181. ASTA

Dona Cooper's American Society of Theater Arts, 612 12th St. NW, is a small space where performances are given Wednesdays through Sundays at 8 and subscriptions are available. Starting next month, the season will include Strindberg's Miss Julie, Schnitzler's La Ronde, Synge's The Playboy of the Western World, Coward's Private Lives and a new "low key" adaptation by Cooper of Bram Stoker's Dracula. Jay Allison also directs its offerings. Further information at 628-8368. WPA

Alice Denny's Washington Project for the Arts, 1227 G St. NW, accents the visual arts but occasionally introduced innovative performing styles in a third-floor open space.Originality is the key here. Information at 347-8304. WAFT

The Washington Area Feminist Theater will be presenting workshops and staged readings during the fall. It headquarters at Summer School Building, 17th adn M Streets NW. Details at 638-0008. Earth Onion

This women's theater, 2416 18th St. NW, offers workshops and performances, usually of originally works; details at 667-3785.