I’m not a financial advisor, just a finance student sharing what I’ve actually done and learned. Do your own research before making any financial decisions.

Most people spend their internship paycheck on rent, going out, and whatever’s left over on things they’ll forget about in three weeks. That’s not a criticism — New York is expensive and internships are short. But if you’ve got earned income coming in for the first time, you’re also sitting on a window that’s genuinely hard to replicate later: the ability to contribute to a Roth IRA when your income is low and your tax rate is almost certainly the lowest it’ll ever be.

I’m finishing up my second summer at a commodities brokerage in New York. I’ve made some deliberate choices about where the money goes and I’ve gotten a few things wrong along the way. This is what I’d tell a friend who just got their first real paycheck and actually wants to do something smart with it.

Start With What You Actually Take Home

The first paycheck I ever got as an intern came with $340 withheld in taxes I hadn’t fully accounted for. I knew there would be withholding — I wasn’t completely clueless — but I had been mentally spending based on the gross number on my offer letter. That gap between gross and net completely recalibrated how I think about budgeting.

Before you allocate a single dollar, pull up your pay stub and understand what you’re actually working with. FICA takes 7.65% off the top automatically. That’s 6.2% for Social Security and 1.45% for Medicare. Federal income tax gets withheld based on your W-4. If you’re a dependent on your parents’ taxes and you filled out your W-4 accordingly, you might get most of that back as a refund, but it’s still gone for now.

The practical move is to build your whole plan around net income. Not gross. Once you know what’s landing in your account, you can actually start making real decisions.

For context on what this looks like in a real city: my first summer in New York, I was taking home about $3,800 a month. Rent was $2,100, groceries and transit ran me roughly $400. That left somewhere around $1,300 to work with. It felt fine. But it required actually knowing that going in.

The Roth IRA Case Is Pretty Hard to Argue Against

If you have earned income from your internship, you’re eligible to contribute to a Roth IRA up to the amount you earned, with a maximum of $7,000 for 2025. You don’t have to max it out. But you should put something in.

The argument for a Roth at this stage is basically about taxes. Right now, if you’re making intern money, your effective federal tax rate is probably somewhere between 10% and 22%. You contribute post-tax dollars now, the money grows for decades tax-free, and you pay nothing when you withdraw it in retirement. Compared to what your marginal rate will likely be at 55 or 60, contributing now is a pretty obvious trade.

I opened my Roth IRA at Fidelity when I was 19. Put in $400 from the first paycheck that felt like real money. The setup took about 20 minutes and was completely anticlimactic. That was the point. I’ve kept my contributions in FSKAX, which is Fidelity’s total market index fund with a 0% expense ratio. Nothing exotic. Just broad market exposure with no annual drag eating into returns.

Fidelity has no account minimum for a Roth IRA and no fees to open or maintain one. If you want to compare your options before committing, this breakdown of Fidelity vs. Vanguard for beginners is worth reading. Both are solid. The differences are smaller than the decision of actually opening one.

This summer I treated my Roth contribution like a fixed bill. Moved $500 over the first week before I touched anything else. Whatever was left was mine to do with. That mental framing matters more than it sounds.

Build the Floor Before You Reach for Returns

There is a version of this advice that jumps straight to stock picks and portfolio allocation. I want to hold off on that for a second.

Before you put money into investments, you need a cash buffer. Not a huge one, but a real one. My rule is three months of essential expenses in a high yield savings account. It’s not exciting, but it makes everything else less fragile.

I keep my emergency fund in a Marcus by Goldman Sachs account, which is currently paying 4.10% APY with no minimum balance and no monthly fees. That’s not an investment, it’s a foundation. The distinction matters because when something unexpected comes up — a medical bill, a busted flight, a gap between jobs — you don’t want to be liquidating investments at an inopportune moment to cover it.

For the actual investing piece, once the buffer is funded and the Roth is open, a taxable brokerage account is the logical next step if you have more to deploy. If you’re not sure what a brokerage account even is or whether you need one at this stage, start there before you open anything. The mechanics are simple but the sequencing matters.

In a taxable account, I’d say the same thing I tell anyone who asks: broad index funds. FSKAX or FZROX at Fidelity, VTI at Vanguard, VOO if you want S&P 500 exposure specifically. Low expense ratios, broad diversification, no stock picking. I bought one individual stock freshman year in a company I thought I understood really well. Sold at a loss eight months later. That was the last individual stock I’ve touched. I’m not saying it can’t work. I’m saying the evidence for it working consistently is pretty thin, and index funds have beaten most active strategies over long enough time horizons.

A Simple Allocation Framework for Intern Money

The exact numbers here depend on your situation, but this is roughly how I think about it.

If you’re bringing home around $3,500 to $4,500 a month from a summer internship and your rent and basics are covered, something like this holds up: contribute enough to hit at least $1,000 into your Roth IRA for the summer, keep $500 to $1,000 in cash reserves if your emergency fund isn’t already solid, and then use whatever’s left for either additional investing or genuine spending. You’re 20 or 21 years old working for the summer. You don’t need to live like a monk.

The thing people get wrong is treating investing and spending as opposites. They’re not. It’s sequencing. Cover the floor, automate what you’ve decided to invest, and then live your life with whatever’s left. Trying to optimize every dollar in real time is exhausting and you’ll abandon the system by July.

On the credit side, if you’re using a card for daily purchases anyway, make sure it’s working for you. I use the Chase Freedom Flex for most spending right now. It has no annual fee, earns 5% on rotating categories and 1.5% on everything else, and the sign-up bonus is currently $200 cash back after spending $500 in the first three months. The variable APR runs from 19.99% to 28.74% but that only matters if you’re carrying a balance, which you shouldn’t be. My first card was the Discover it Student, which I still have open. It’s worth keeping for credit history length even if you graduate past it.

One thing I’d also flag: if your employer offers any kind of 401k match, even for interns, contribute enough to capture it. Free money with an immediate 100% return is the clearest investing decision that exists. Not all internship programs offer this but some do.

For anyone looking for an investing app to actually execute this through, this comparison of investing apps for college students lays out the real options without a lot of noise.

The broader point is that an internship paycheck is a rare opportunity to build real habits with real stakes while the dollar amounts are still forgiving. Getting a Roth IRA open, understanding your take-home pay, and automating even a small contribution are worth more in the long run than almost any specific investment decision you’ll make in these three months.

Frequently Asked Questions

Q: Can I contribute to a Roth IRA if I’m still claimed as a dependent on my parents’ taxes? Yes. Dependent status has no effect on Roth IRA eligibility. You just need to have earned income and fall under the income limits, which for 2025 begin phasing out at $150,000 for single filers.

Q: What if I don’t earn enough from my internship to max out the Roth IRA? You can contribute up to the amount you earned, even if that’s less than $7,000. If you made $4,000 over the summer, you can contribute up to $4,000. Something is always better than nothing.

Q: Is it better to invest in my brokerage account or pay down student loans over the summer? It depends on the interest rate on your loans. If you’re carrying federal loans at 5% to 7%, it’s genuinely close. High-interest private loans above 7% or 8% probably deserve priority. Federal loans in the 4% to 5% range are a tougher call and reasonable people disagree.

Q: Should I invest my internship money in individual stocks or index funds? Index funds. Especially at this stage. A total market fund like FSKAX or VTI gives you broad diversification with no expense ratio drag and no need to track individual companies. You can always add complexity later once you have a real foundation.

Q: How do I actually open a Roth IRA if I’ve never invested before? Go to Fidelity.com or Vanguard.com, click “Open an Account,” and select Roth IRA. You’ll need your Social Security number, bank account info for the initial transfer, and about 15 minutes. There’s no minimum to open at Fidelity. The process is genuinely less complicated than most people expect.