Bride-to-be Patrice McGraw of McLean hasn't planned all the details of her August wedding yet, but she and her fiance' already have agreed on a few extras -- a live band, an open bar and a honeymoon suite in one of the best hotels in town for their first night of married life.

"We both work full time, so we are willing to chip in for the things we think will really make it nice," said McGraw, 26, an assistant director for a national association in the District.

McGraw is the type of bride -- older and with an income of her own -- who has provided a bonanza for the wedding industry in the past few years, according to officials from bridal industry magazines and associations.

The wedding industry, which covers everything from silverware to honeymoon travel, has increased its U.S. sales from $15 billion in 1977 to $20.1 billion in 1983, as brides have shifted back to large-scale, traditional weddings.

Spending jumped 34 percent even though the number of weddings increased only about 5 percent (to 2.4 million a year) during the same period, according to a report published by Brides magazine in New York.

Several factors have contributed to the increase in the wedding business, including the fact that couples planning weddings tend to be older and more affluent. A 1984 survey by the magazine found that the average income of newly married couples when both work is a comfortable $40,400. The same survey found that the average age of brides had risen from 19 in 1961 to 23 in 1983. More than one-fifth of all brides today are over the age of 25.

At the same time, large, traditional weddings have become more fashionable, replacing the homemade vows and simple garden weddings in vogue in the late '60s and '70s.

"For a good decade or so, we were really out of fashion, and some in the industry took a beating," said Brides magazine editor Barbara Tober. "But now we've taken a swing back to a more traditional view of big weddings and lots of celebration. Advertising is way up, and a lot of businesses that overlooked the bridal market are starting to tap into it."

Tim Johnson, owner of Old Town Catering Co. in Alexandria, has been planning wedding receptions since he started the business four years ago. Like many caterers, he will order invitations, pick up flowers, hire a limousine, book a band and provide a photographer, as well as feed guests for wedding receptions of any size or style.

"Any major city like Washington has a concentration of professionals," he said. "If you figure two lawyers are getting married and each earn $40 to $50 an hour, then it is financially beneficial for them to have someone else see to the details after they make the decisions."

Johnson, who started advertising specifically for bridal market only this year, estimates that about 60 percent of his business is weddings. He said guests at weddings he has catered may look up Old Town Catering Co. when it is time to plan their own weddings.

The role of a company such as Old Town Catering in planning a wedding is the sign of another change in the industry. Paid consultants increasingly are assuming the tiresome tasks traditionally performed by the bride's mother.

"Because most brides work now, they don't have time to do all the planning for a wedding," said Tober of Brides magazine. "Also, a lot of brides have moved from home, and their mothers are not nearby to help. So department stores and caterers are stepping in, offering complete packages of flowers, dress, food and photographer."

Future bride Leah Bromser, 24, busy studying with her fiance' Martin Cloeden, also 24, for law exams they will both take at Catholic University this spring, is shopping around for a caterer who will handle all the details for her June wedding at an estate in Virginia.

"My mother lives in Texas," said Bromser, who moved to the District to attend school and met her future husband the first day of classes. "If she were here, then I would probably depend on her more. As it is, we've gone to five wedding shows and have a good idea of what we want. Now I just need someone to help me with the logistics."

And there are plenty of area businesses ready to help.

Ed Solomon, for example, sells wedding gowns in his Georgetown store, Wedding Creations, but he also offers a long list of additional wedding services.

Couples getting married "would rather go with one person they trust than try to deal with a lot of professionals they're not sure of," said Solomon of the increasing number of couples who do one-stop-shopping at his store. "The other great advantage is that they can leave one deposit that will cover gowns, photographer, flowers, caterer and everything else.

"Brides now are professionals," he said. "They're smart. They want to save in one area, for instance a dress with a less expensive material, so they can splurge on a really terrific honeymoon or good food at the reception."

Department stores, once the bastions of bridal wear, also are beginning to offer wedding services, Tober said. In the past two decades, the bulk of wedding gown sales have shifted to specialty bridal shops, according to industry statistics. Department stores have been forced to either close their bridal salons or keep pace with the changing industry.

Woodward and Lothrop is one of the few department stores in the area that kept and expanded its bridal departments despite the decline in business in the late 1960s and 70s.

The seventh-floor bridal shop at Woodward and Lothrop's downtown store was transformed recently into a living advertisement for the department store chain's one-stop-wedding-shop services.

As models wearing clothes from Priscilla of Boston's 1985 collection swayed down the runway, a four-piece wedding band lulled brides-to-be with its own rendition of "Here Comes the Bride."

After the show, there were tables with wedding cakes baked by Woodies, sample wedding invitations engraved for Woodies, even coupons offering $5 off on haircuts by Woodies' salons for the entire wedding party.

The five wedding consultants at the downtown store offer newlyweds-to-be everything from gowns and tuxedo rental to videotaping of the wedding services, an in-house travel agent, a computerized bridal registry and listings of companies providing horse-drawn carriages.

Despite the extras, it is the bridal registry that makes the most money for department stores. Over half of the industry's revenue comes from sales of furnishings, china and other items sold as wedding gifts. On the day of the show, Woodies registered 200 brides-to-be, sending gift lists electronically to 14 of its 15 area stores.

"When a bride and groom register with us, hopefully, they will be a Woodies customer for the rest of their life," said Gigi Warren, manager of Woodies' wedding service and bridal registry departments.

In 1984, Woodies registered 6,400 couples, a 9 percent increase over the 5,900 couples registered in 1983. A national study for Modern Bride and Brides magazines found that bridal registries generated sales of an average $3,600 per couple in 1984 and that the figure may rise to between $4,800 and $7,000 per couple in 1985.

Warren attributes the growth in registry sales to the fact that better-educated, older couples who already have set up housekeeping know exactly what they need. Today, many brides-to-be bring their fiance's to register with them, and the couples are choosing less conventional gifts. Recently, Warren said, she had one couple register for downspouts for their home, while another couple registered for a lawn mower.

Industry representatives are reluctant to put a price tag on the average wedding because, they say, it depends on the area of the country and the number of guests. But a 1983 survey for Brides magazine set the figure at about $7,800 for a wedding ceremony and reception for 200. Of the weddings this year, 800,000 will be of couples remarrying after being divorced or widowed. These ceremonies usually are less elaborate than first-time weddings, said Tober, who remarried several years ago, but it is now increasingly acceptable to have a ceremony and sizable reception the second time around.

But Tober and other industry representatives agree that career couples getting married for the first time are the main target for wedding businesses and services.

"Usually, couples today have been working for several years and are willing to pitch in to make it a memorable day rather than have the bride's parents shoulder the whole cost," said Nancy S. Dver, co-founder of the Bridal Industry Association.

"I'm 30 years old, and it seems silly to ask my parents to pay for a wedding," said Kate Wolfe, who is planning to marry Steve Labuda, 31, in October.

Wolfe hopes to marry in a garden, they are planning a honeymoon in the Caribbean, and she wants a chocolate wedding cake with chocolate icing.

"I think I'm like most brides who have been on their own," she said. "I have a certain stamp I want on my wedding, my own individuality. It's worth a certain cost, although I'm not planning on going into debt over it."

Atoussa Navab, 25, a conference coordinator for a nonprofit education association, disregarded her careful budget to splurge on an elegant designer wedding dress with a sweeping train that she says makes her feel like a princess.

"I decided to choose a better-quality dress that I like," she said. "You don't want to spend so much for one day, but it's the only day like it I'll ever have."