I work for a Fortune 500 company and my commission is treated just like my base income. They withhold the taxes when they cut me my check. I think that is the standard practice with most employers.
I am neither a salesperson nor a tax pro, but I'll throw in my $.02 anyway . . . I've had some friends who were in sales in the past and remember them talking about how taxes were withheld at a higher rate than if they were straight salary. I guess this is done to deal with the ups and downs of commission, but certainly isn't ideal. The good news is that you probably end up with a big refund. The bad news is that you've got less money in each paycheck.
for years it used to be our commish came on one check and pay came on another, both taxed in accordance with our deductions we select, now we've been bought out by a fortune 500 company and our commish MUST be taxed at 25% because it is considered "additional income" and your deductions don't mean a thing on the commission, it's 25% no matter what.
they tell us that is the law but I think it's 100% bullshit.
Your employer is basically full of it (sort of). Here's how it works.
Federal tax withholding is figured on a per-paycheck basis. Let's say you are on commission and only make your base this paycheck - let's say $500. The withholding on $500 (assuming no allowances) is $45.55. You will of course have social security and medicare (FICA) withheld in the amount of $48.25 (7.65%).
The next paycheck you had a great period. Let's say you get your base plus $2,000 commission, for a total of $2,500. If the employer lumps the commission in with your base pay (doesn't identify them separately) then your total tax withholding is 471.55. Notice how the percentage is higher - the withholding rates are structured pretty much like the tax tables (15% up to x, 25% on the excess up to y, etc). What's key here is the "if" the employer lumps the commission in with your base pay. They don't have to.
However, if your employer identifies commissions separately, then they can (can - not have to) withhold a flat 28% on your commission.
If you find that the withholding on your commission rate is too high - increase your allowances on your regular check to compensate.
Cameron, do you have any resources that I might be able to show them?
All of my coworkers are upset about this and accounting is completely unwilling to change or look at alternatives, in fact here is their explanation directly.
Your explanation is spot on. One period I get my $XXXX base, and the next I get my XXXX base plus my comission for the month and they do divide it out on the statement as salary and commission.
I had completely forgotten about this, but I used to have a sales job where my salary was always less than 50% of my income, and in a good year, it could be as little as about 20%. My employer did not offer the option to lump salary and commission together. We got our salary every 2 weeks and commission once a month. I seem to recall most of the salespeople had little or no withholding on their salary to compensate for the excess commission withholding. Even at that, I always got at least 3 or 4K refund at the end of the year. On my last commission check (this was Jan 1994) the required withholding increased to a flat 50%!!! It was supposedly a new requirement from the IRS that year.
Path of Least Resistance: The payroll/accounting folks will follow the method that is the least amount of effort for them.... which is probably the flat percentage deduction. Good luck trying to get them to change.
Whoops - looks like what I was looking at was a little dated. My 28% is actually 25% - but everything else looks about right.
[The following assumes a single person with no allowances]
The reason the IRS allows for the separate identification and withholding on supplemental wages is actually to make it more fair for the employee. Basically, if I get a big commission check / bonus /etc one pay period (let's say $15k), under the standard withholding tables the employer would have to withhold 33% of that. Essentially, the withholding tables assume that whatever you make this period is consistent with the rest of the year. Larger one-time payments essentially result in over-withholding if you aggregate the supplemental payments in with regular salary.
Also - while the link Seth provides is in the Government Entity section of the IRS website, the same rules apply for regular employers as well. Supplemental income is discussed on page 13 of this publication - http://www.irs.gov/pub/irs-pdf/p15.pdf