How to open a children’s investment account in 2026 — provider comparison
A custodial brokerage account is the most powerful long-horizon vehicle a family can use. Children get their own tax allowances, and an 18-year compounding window turns small monthly contributions into life-changing balances. $100 a month for 18 years at 7 % grows to roughly $45,000; $200 to $90,000. This guide compares the standard providers, walks through the tax mechanics, and flags the typical mistakes parents make.
What is a custodial / children’s investment account?
A custodial account is a brokerage account opened in the child’s name, with a parent or guardian as legal custodian. Money belongs to the child legally — parents administer it until the age of majority.
- Ownership: The child owns the assets from day one. Parents cannot withdraw for personal use.
- Administration: The custodian (parent) makes investment decisions until the child reaches the age of majority (18 or 21 depending on state).
- Use of funds: Until majority, only “for the benefit of the minor” — education, first car, college, starting an apartment. Family vacations or parental purchases are a fiduciary breach.
- Handover: At majority age, the child gets full legal control. There is no opt-out.
Account types — UTMA / UGMA / 529 / Custodial Roth IRA
| Type | What it is | Tax treatment | Best for |
|---|---|---|---|
| UTMA / UGMA | Generic custodial brokerage; can hold any security | Kiddie tax: first $1,300 free, next $1,300 at child’s rate, above at parent’s rate | General-purpose savings; flexible use |
| 529 Plan | Education-only savings; state-tax deductible in many states | Tax-free growth + tax-free withdrawals if used for qualified education | Specifically for college / K-12 tuition |
| Custodial Roth IRA | Roth IRA in child’s name; requires earned income | Tax-free growth + tax-free withdrawals after 59.5 | Teen with summer/part-time job income |
| Coverdell ESA | Education savings account; $2,000/yr cap | Tax-free growth for education | Smaller education-focused contributions |
The most common combination for a child born today: UTMA for general savings + 529 for education-specific funds + Custodial Roth IRA once the child has earned income from a summer job.
At 7 % nominal expected return (S&P 500 long-run average) and 18 years, $50/month compounds to ≈ $22,700, $100/month to ≈ $45,400, $200/month to ≈ $90,800.
Concrete numbers — what does each contribution level become?
| Monthly contribution | Total deposited (18 yrs) | Balance at 5 % | Balance at 7 % |
|---|---|---|---|
| $25 | $5,400 | ≈ $8,700 | ≈ $11,300 |
| $50 | $10,800 | ≈ $17,400 | ≈ $22,700 |
| $100 | $21,600 | ≈ $34,800 | ≈ $45,400 |
| $200 | $43,200 | ≈ $69,500 | ≈ $90,800 |
| $500 | $108,000 | ≈ $173,800 | ≈ $227,000 |
Using child tax credit / monthly child benefit (where applicable) as the funding source is the cleanest mental model — the money is earmarked for the child anyway, redirecting it into a long-horizon ETF builds a six-figure base by age 18.
Provider comparison 2026
| Provider | Account types | Min. to open | Fees | Notable |
|---|---|---|---|---|
| Fidelity | UTMA, UGMA, 529, Roth IRA | $0 | $0 commission, $0 account fees | Best all-rounder; fractional shares; strong app |
| Charles Schwab | UTMA, UGMA, Custodial IRA | $0 | $0 commission | Strong customer service; no 529 directly |
| Vanguard | UTMA, UGMA, 529, Custodial IRA | $0 (some funds: $1,000) | $0 commission, low ETF expense ratios | Best for buy-and-hold ETF investors |
| E*TRADE | UTMA, UGMA, Custodial IRA | $0 | $0 commission | Decent platform; owned by Morgan Stanley |
| Greenlight | Custodial brokerage + debit card | $0 (subscription $5–15/mo) | Subscription fee, no trading fees | Education-focused; for teaching kids |
| Acorns Early | UTMA / UGMA | $5 | $5/month subscription | Auto round-up investing; high fee per dollar invested |
For most families, Fidelity is the cleanest choice — zero fees, all major account types, fractional shares, and a 529 if you go that route. Schwab and Vanguard are equally solid alternatives. Subscription-based apps (Acorns, Greenlight) are educationally useful but cost-inefficient at low contribution levels.
Opening the account — 5 mandatory steps
- Gather child’s documents. Social Security number is mandatory in the US. Birth certificate is sometimes requested. The custodian needs their own SSN and government ID.
- Open the account online at the chosen broker. UTMA/UGMA accounts open in 5–10 minutes; 529 plans take longer because they go through state-sponsored programs.
- Set up funding. Bank transfer (ACH) is free and standard. Set up an automatic monthly contribution — the entire compounding game is about not skipping months.
- Pick the investments. For an 18-year horizon, equity index funds belong in the high-90s percentage of the allocation. VTI, VXUS, VT, or a target-date fund are the conventional picks.
- File a tax return for the child if needed. Once unearned income exceeds $1,300/year, the child needs Form 8615 attached to a return (kiddie tax). Above $2,600, parent’s tax rate applies. Many families never hit these thresholds.
Which ETFs fit a child’s account?
With an 18-year horizon, an equity weight of 90–100 % is mathematically appropriate. Standard picks:
- VT (Vanguard Total World) — single-fund global solution, ~9,000 stocks, expense ratio 0.06 %
- VTI + VXUS — separate US (VTI) + international (VXUS), classic 70/30 or 60/40 split, expense ratios 0.03 % / 0.07 %
- VOO / IVV — S&P 500 only, expense ratio 0.03 %, US-only concentration
- Target-date 2040/2045 fund — auto-glidepath, fire-and-forget; expense ratios 0.08–0.15 %
Avoid actively managed mutual funds with 0.5–1 % expense ratios — over 18 years that drag costs $5,000–$15,000 per $100,000 of contributions.
Common mistakes with custodial accounts
- Automate contributions — monthly ACH, no exceptions
- Use index funds only — VTI/VT/VOO with 0.03–0.06 % expense
- Make grandparent gifts go directly into the account
- Talk to the child from age 14 — financial literacy is the real gift
- Plan the handover — joint conversation 6–12 months before majority
- “Borrowing” from the account — fiduciary breach, legal exposure
- Concentrated positions in single stocks (Tesla at 18 in a crash)
- High-fee actively managed funds — 1 % vs 0.05 % is a $30k difference at 18
- UTMA balances reducing financial-aid eligibility (counted at 20 % vs 5.6 % for parent assets)
- Trying to “take it back” at 18 — legally impossible, will damage the relationship
FAQ
Who actually owns the money in a custodial account?
The child — from day one. Parents are fiduciaries with legal duties to act in the minor’s best interest. Once the child reaches the age of majority (18 or 21 depending on state and account type), they get full legal control. Trying to “claw it back” later is not legally available.
What is the kiddie tax and how does it work?
For 2026, the first $1,300 of a child’s unearned income is tax-free. The next $1,300 is taxed at the child’s rate (typically 10 %). Anything above $2,600 is taxed at the parent’s marginal rate to prevent income-shifting. With $100/month contributions and modest dividend yields, most custodial accounts stay below the kiddie-tax threshold for many years.
How does a custodial account affect financial aid?
UTMA / UGMA balances count as student assets on the FAFSA, which are assessed at 20 % per year — much harsher than the 5.6 % rate on parent assets. A 529 plan owned by the parent is treated as a parent asset (much friendlier). For families with a likely significant aid claim, putting growth in a parent-owned 529 instead of a UTMA can preserve thousands in aid eligibility.
UTMA or 529 — which is better?
Different jobs. 529: tax-free growth and tax-free withdrawals for qualified education; state-tax deduction in many states; non-education withdrawals trigger penalty. UTMA: flexible — can be used for anything in the child’s interest; no penalty; but balance becomes child’s property at majority. Many families do both: 529 for tuition, UTMA for everything else (first car, gap year, deposit on first apartment).
Can a child get a custodial Roth IRA?
Yes, but only if the child has earned income — wages from a summer job, modeling, babysitting reported as self-employment, etc. The annual contribution cap is the lower of $7,000 (2026) or the child’s earned income. A teenager who earns $3,000 from a summer job can have $3,000 contributed to a Roth IRA — at 7 %, that single year compounds to roughly $300,000 by retirement.
What about the gift tax?
The 2026 annual gift-tax exclusion is $19,000 per donor per recipient. Two parents can therefore gift $38,000 per year per child without filing a gift-tax return. Grandparents add another $19,000 each. For routine $100–$500 monthly contributions, gift tax is essentially never a concern.
Should I really start a child’s account from infancy?
Yes — the earlier the better. A monthly contribution that starts at birth has the full 18-year compounding window. Starting at age 10 cuts the runway in half and roughly halves the end balance. If you’re unsure whether to start with $25 — start with $25. You can always increase later, but lost time never comes back.
Run the contribution math, real return, and broker comparison
Before you set up the recurring deposit, it pays to see the actual numbers — what does $100/month become in 18 years, what’s left after inflation, and which ETF mix makes sense for an 18-year horizon?
- DCA simulator — historical paths for $50/$100/$200 monthly contributions
- Real-return calculator — what stays after inflation across 18 years?
- Best broker for recurring investments — direct comparison on BMI
- ETF comparison — VT vs VTI+VXUS vs VOO for a long-horizon plan