Start investing before you feel ready. The market doesn't require your confidence. The amount doesn't need to be large. What costs you the most is waiting.
I've spent 15 years managing finance professionally. The single most common mistake I see people make in their personal finances is not starting soon enough. Not the wrong fund, not the wrong allocation, not the wrong brokerage. Just not starting. And the math is brutal.
The number that should make you uncomfortable
Assume you invest $300 per month at a 7% average annual return. That's a reasonable estimate for a low-cost index fund held over a long period.
$300/month at 7% annual return
Starting at 25, retiring at 65
$798,000
Starting at 35, retiring at 65
$363,000
Starting at 45, retiring at 65
$156,000
Same $300/month. Same 7% return. The only variable is when you start. Waiting 10 years cuts the outcome by more than half.
The gap comes entirely from time, not investment skill. Returns generate their own returns. With more years, that compounds further. Waiting 10 years doesn't reduce your outcome by 25%. It cuts it by more than half.
The amount matters less than you think right now
Most people delay because they think they don't have enough to invest. I understand that instinct: putting $50 into a brokerage account when rent is due feels pointless. The math says otherwise.
At 25, the most valuable thing you have is time. Time is the input compounding runs on. A smaller amount invested today is worth more than a larger amount invested 5 years from now, because every year it compounds is a year you can't get back.
The amount you invest matters. The time you invest matters more.
The goal at 25 is to build the investing habit before you've talked yourself out of it. The habit is the asset.
What to actually do
If your employer offers a 401(k) with a match, start there. Contribute at least enough to capture the full match. That's a guaranteed 50% or 100% return on the matched portion, before any market gains. A 100% return on day 1 exists nowhere else.
Once you've captured the match, open a Roth IRA if you're eligible. Early in your career, your tax rate is likely lower than it will be later. A Roth lets you pay taxes on contributions now and owe nothing on withdrawals later. At current rates, that's usually the better deal. The 2026 contribution limit is $7,000 per year. Roth IRA eligibility phases out above certain income thresholds, and contribution limits are set annually by the IRS. Verify current limits and your eligibility at IRS.gov or with a tax advisor before contributing.
For what to invest in: a total market index fund. I'll cover exactly why in the next article. For now, the decision tree is simpler than the financial media wants you to think: get the employer match, open the Roth, buy the index fund, and leave it alone.
The one thing worth repeating
Every month you wait is a month of compounding you can't recover. That's arithmetic, not a scare tactic. The money you invest at 25 will outperform any raise or bonus you receive later, simply because it has more time to compound.
Open an account. Put something in it. Let time do the work.
Start before you're ready. The version of you at 65 will be grateful you did.