It’s summertime, and I’m sure the last thing you probably want to think about is taxes.

Well, think again. Even though most of us are trained to begin the taxing job of tackling our tax returns after the first of the year, constant changes to the tax code are almost making it a year-round job.

So, put down your beach book just for a little while and take the time to check a few things.

For instance, make sure your paycheck is a little fatter now, advises Arizona-based Symmetry Software, which runs a Web site with a great calculator that can help you check how the new tax law will affect your bottom line.

You should have more money as a result of lower tax rates, thanks to the Jobs and Growth Tax Relief Reconciliation Act of 2003.

Employers should have started using the new rate tables no later than July 1. The old federal tax rates of 27 percent, 30 percent, 35 percent and 38.6 percent have been reduced to 25 percent, 28 percent, 33 percent and 35 percent respectively. This is a drop of two percentage points for the first three rates. The fourth, called the top bracket, went down 3.6 points.

Since employers had just a few months to apply the new rates, Sam Kerch, senior tax research analyst for Symmetry Software, suggests you double-check your pay stub to make sure you’re getting the right amount.

“It’s not likely there is a mistake, but it could be because everything had to be done so quickly,” Kerch said.

Besides, this double-check is free. Just go to Symmetry’s Web site at www.paycheckcity.com and click on the link that says, “New 2003 tax cut calculator.” You will need to have your paycheck stub and know how many withholding allowances you elected on your federal and state W-4 forms.

So, for example, let’s say you live in California and have a gross income of $60,000 a year, you’re paid biweekly, married and have five federal and state exemptions.

Before the tax cut, your take-home pay (not including various other withholdings you might have elected) would have been $1,862.63, according to Symmetry’s calculator. Your net pay should have increased to $1,877.43 after the tax cut.

Just so you know, the tax cut is retroactive to the beginning of this year, so many taxpayers will have had too much withheld from their pay for the first half of 2003.

As a result, you may need to change the number of withholding allowances you take, Kerch said. That means filling out a new W-4 form, which you can also do on Symmetry’s Web site or at www.irs.gov.

As Kerch points out, if too much was withheld, you may end up with a large tax refund.

“A big fat refund check is a big fat interest-free loan to the government,” Kerch said.

You can adjust your withholding at any time to increase your take-home pay by claiming allowances based on expected tax deductions and credits.

Just follow the instructions on the W-4. It’s really not hard.

On the other hand, you may want to reduce your withholding allowances to make sure you don’t have to pay additional taxes come April 15.

“A tiny refund or a tiny tax payment should be your objective,” according to Kerch.

Here are a few more summertime tax tips from the IRS:

• If your child is in a summer day camp, the cost counts as an expense toward the child and dependent care tax credit. This credit is available to people who, in order to work or to look for work, have to pay for child care services for dependents under age 13. The limit on the amount of qualifying child care expenses increases this year to $3,000 for one child and $6,000 for two or more children. (The amount for 2002 was $2,400 and $4,800 respectively.)
• If you’re a student working for the summer, the IRS wants to remind you that you may be exempt from federal withholding if you can be claimed as a dependent (such as on your parent’s tax return); your total 2003 income will not be more than $4,750; you won’t receive more than $250 in interest or dividend payments (otherwise known as unearned income); and you didn’t have to pay income taxes last year. However, you still have to pay Social Security and Medicare taxes.