If you're headed to college this fall and you haven't filled out an application for federal financial aid, you might want to complete it soon.

The Free Application for Federal Student Aid (FAFSA), which you can file as early as Oct. 1 of the year prior to entering college, determines not only how much you can get in federal grants and loans (as well as aid for work-study programs) but also how much financial aid most states and colleges will offer you. 

In several states, aid is given on a first-come, first-served basis, and many states have winter deadlines that are coming up fast. Some colleges also give priority to early filers. 

More About Paying for College

This is the second year that college students have been able to file for financial aid as early as Oct. 1 of the year prior to entering college. Before that FASFA couldn't be filed until Jan. 1 of the same year a student entered college.

As a result, FAFSA forms are flowing in earlier.

"There's always competition for financial aid, and since the FAFSA is available earlier, it's more important than ever to complete your application as soon as you can," says Kathy Ruby, director of college finance for College Coach, a college admissions consulting firm.

There could be another benefit to filing the form early. Some schools are now processing admission decisions and aid applications earlier, Ruby says. That could give you more time to consider the financial aid offer a school gives you and weigh your options before deciding which school to attend. 

Follow these tips to make the FAFSA application process smoother.

Apply, Even If You Don't Think You Qualify

As many as 2 million students a year who are probably eligible for aid don't even apply, according to a report by the Bill and Melinda Gates Foundation. 

One reason is that people assume they make too much money to qualify for financial help. While your income is a factor in determining the amount of need-based aid you can get, there isn't a specific earnings cap. Even upper-income families can sometimes qualify, depending on a number of factors, including where the student is applying.

In general, at a state university you're probably not going to qualify for need-based aid if your household income is over $100,000 a year, says Shannon Vasconcelos, a college finance consultant for College Coach and former financial aid officer at Boston University and Tufts University. But at a more expensive private college, you may be eligible for need-based aid even if your income is up to $200,000, she says.

The number of children in a family and how many are enrolled in college at the same time also make a difference. So does the age of the parents with a dependent student. For older people, a larger portion of nonretirement savings is excluded from the financial aid calculation. (Retirement savings such as 401(k)s aren't counted at all under the federal aid formula.)

Keep in mind that no matter what your financial situation, you can always get a federal student loan. Even if you don't want to borrow now, you'll be glad you filed FAFSA if there is a change in your financial circumstances, such as a job loss or an unexpected medical expense that could make you eligible for additional aid.

"Some colleges won't consider a request for assistance after the deadline if you didn't apply initially," Vasconcelos says.

Gather Financial Documents

When you fill out the application, you'll need your 2016 tax return, W-2s, bank statements, and account records of other financial assets. You'll need what's known as a FAFSA ID to access the federal financial aid portal to fill out the application.

Even if you're a dependent on your parents' tax return and need to submit their information, both you and a parent need FAFSA IDs to access the site. 

If you're returning to school, you have to file a FAFSA every year to get financial aid, and you may have to update your password because it expires every 18 months.

Even if it's not the first time you're filling out the form, you may need to wait one to three days for the account verification process before you can use your FSA ID to renew your FAFSA form and sign it online.

Know Your Deadlines

A number of states have early winter deadlines for the grants and scholarships they give out. In Tennessee, for example, applications for some state grants are due Jan. 16. In Connecticut, all financial aid applications are due Feb. 15. 

At least six states, including Alaska, Illinois, Washington, and Kentucky, have no hard deadlines. They award money until funds run out. (Find state deadlines here.)

For federal financial aid, you can apply with FAFSA until the end of the academic year you're enrolled in school. (That's June 30, 2019, for the 2018 to 2019 year.) But consideration for programs such as work-study is given to those who apply earlier, so sooner is better for federal aid, too.  

File Online

FAFSA is long—about 100 questions—but the Department of Education has worked to streamline the process online. It estimates that it should take about 30 minutes to complete.

The online application uses "skip logic," so you see only the questions that apply to you, rather than sifting through many questions you don't need to answer on the printed version.

You can also cut down on mistakes by using the IRS data-retrieval tool, which automatically imports information from your tax returns. The tool was offline for a few months last year because of data security problems, but the IRS says it fixed the problem. 

Fill Out Other Forms as Needed

Several hundred private schools, a few public universities, and some scholarship programs also require an additional financial aid form, the CSS/Financial Aid Profile, to calculate the grants, loans, and scholarships they give out.

The CSS asks for more detailed financial information. For example, while the FAFSA will use only 2016 tax-year information this year, the CSS Profile asks for projections of your 2017 and 2018 income. Make sure the information on the CSS matches what's on your FAFSA. And check your school's financial aid website to see whether it's required.