It’s a rite of passage for up-and-coming Wall Street bankers to do tours of duty overseas. But this year they are stewing because the dollar’s decline means the greenback-based bonuses they are about to collect will buy a lot less than if they were based back home.

Goldman Sachs Group, Merrill Lynch & Company, Credit Suisse First Boston Corporation, and most other banks pay salaries and, more importantly, bonuses, in American dollars to high-level employees no matter where they’re based. With the greenback at historic lows against the euro and in a steady swoon against the British pound and Japanese yen, expatriates and colleagues permanently based abroad are not happy.

“Many non-U.S.-based bankers will be very upset” with bonuses this year, said the head of the global financial services practice at Sibson Consulting in Princeton, N.J., Marc Baranski.

Bonuses, which are often many times more than the base salary for most bankers, traders, and other Wall Street professionals, are paid from mid-December through early February at most major American-based banks, which typically have 25% of their employees based abroad.

Several this year offered their expatriates a chance to lock in dollar-to-local currency conversion rates, bank spokesmen said. But they wouldn’t comment on how many bankers took the bet that the dollar would decline, and several employees said they resented having to make the wager.

“If I were living in the States, I wouldn’t have a problem,” said a European banker who works for an American bank in London and expects a bonus of between $800,000 and $1 million for work this year. “I’m the one who’s suffering.”

His bonus will be worth about 20% less because of the dollar-to-pound conversion, he said. While he had an opportunity to hedge the conversion rate earlier this year, he complained that “you can never remove the risk entirely.”

The dollar on Friday touched an all-time low against the euro, traded last week at more than a 10-year low against the British pound and has been on a steady slide against the Japanese yen.

Not everyone sympathizes with the expatriates, however, even though they are in the second consecutive year of a weak dollar. “Even with a 20% discount, the comp is likely to be as good as local competitors get overseas,” said a New York-based pay consultant, Alan Johnson, who noted that American banks pay higher compensation than most local institutions in financial capitals such as London and Tokyo.

Employees who are permanently based abroad, including many bond and currency traders, have more reason to grouse than do temporary expatriates who get “lavish” extras during tours of duty that typically last three years, he said. Perks include cost-of-living allowances, tax benefits in high tax countries, paid trips home several times a year and, sometimes, paid apartments and private schooling.

Banks would be foolish to primp bonuses in weak-dollar years, he said, because “once you go down the slope of ‘We’ll do something extra for you,’ it’s never-ending,” Mr. Johnson said.

The currency sting is nevertheless a little sharper this year because a greater proportion of bonuses will be paid in cash than in stock or options, said Sibson Consulting’s Mr. Baranski. Profits at American banks are on the upswing, and the companies tend to reward employees with more cash when there’s more of it on hand.

Some banks have acknowledged the currency differential this year.

A spokeswoman for Merrill Lynch said the majority of its overseas employees are paid in local currency. “If they are not, they are given a choice” early in the year of what currency to be paid in, she said. Merrill also lets dollar-based employees lock in exchange rates early in the calendar year, she said.

Bear Stearns Cos. controls the risk for some employees by establishing a “collar” that limits the exchange variations, a person close to the company said. A Bear spokesperson didn’t return calls for comment.

A Goldman spokesman wouldn’t comment on specifics of the firm’s compensation for overseas employees, but said, “We will appropriately protect our international employees against currency fluctuations.”

Expats based in London, meanwhile, have a few new concerns about their pay. Chancellor of the Exchequer Gordon Brown warned in his annual prebudget speech last Thursday that the government plans to crack down on complicated compensation packages that use mechanisms such as offshore payments and dividends to avoid taxes. Brown indicated that the new legislation, scheduled for introduction next year, could be applied retroactively.