Robo Advisor Fee Comparison

1. Enter your initial investment (starting balance).
2. Enter the monthly contribution you expect to add.
3. Set an assumed annual return before advisory fees (a long-term planning rate, not a guarantee).
4. Set Robo A as the lower advisory fee percent and Robo B as the higher fee percent.
5. Choose how many years you plan to stay invested.

The calculator grows your portfolio with recurring contributions at a net return equal to the gross return minus each advisory fee. It then subtracts the two ending balances to show fee drag — money you keep by paying the lower fee, all else equal. Checkpoint rows compare the paths at selected years. Fund expense ratios and trading costs are not modeled unless you fold them into the fee inputs yourself.

Net return A = Gross return − Fee A
Net return B = Gross return − Fee B
Fee drag = Future value(A) − Future value(B)

Start with $50,000, add $500 per month, assume an 8% gross annual return, compare 0.25% versus 0.50% advisory fees, and invest for 20 years. Both portfolios compound, but the higher fee quietly reduces the net growth rate by another quarter point each year. By year 20 the lower-fee path finishes ahead by the “fee drag” amount shown in the results — often a meaningful five-figure gap on this contribution pattern, even though 0.25% sounds tiny in isolation. Stretch the horizon toward 30–40 years and the gap usually widens further. Features bundled into a higher fee (for example tax-loss harvesting) may still be valuable; this tool only prices the fee difference, not service quality.

Robo A / Robo B final value

Hypothetical ending balances after contributions and net-of-fee compounding for each fee level.

Fee drag (A vs B)

How much more wealth the lower-fee path accumulates versus the higher-fee path under identical assumptions.

Fees paid (A)

A simplified illustration of cumulative advisory cost on the lower-fee path — not an invoice from a provider.

Year-by-year comparison

Snapshots showing when the fee gap becomes noticeable along the way.

• Comparing advisory fees while ignoring fund expense ratios inside the portfolio.
• Assuming the higher-fee service has identical net returns before fees.
• Using an unrealistically high gross return that masks fee sensitivity.
• Naming competitor platforms’ current prices without verifying their live fee schedules.
• Forgetting taxes, cash drag, or account type differences when shopping providers.

Identical gross returns, contribution schedules, and time horizons for both fee paths. Advisory fee is subtracted from return each year in a simplified net-return model. No taxes, no rebalancing costs, no cash buffers, and no platform-specific bonuses. Labels “Robo A/B” are generic fee levels — not endorsements of named companies. Hypothetical only.

• SEC Investor.gov — Fees and expenses
• SEC Investor.gov — Compound interest
• AlgoFinanceLab — Robo advisor guides

Dig deeper with our robo advisors comparison and how they work, or try Position Size Calculator and Portfolio Rebalancer.

Estimates only — not financial, lending, or investment advice. Decisions should be based on your full situation and professional guidance where appropriate.