Interactive Brokers vs Fidelity 2026: Fees and Margin Rates Compared

Fidelity and IBKR Lite both charge $0 on online US stock and ETF trades, so an index buyer pays nothing at either; the real gap is borrowing. On a $50,000 margin loan, IBKR Pro charges 5.380% against Fidelity's 10.625%, which is $2,622.50 less interest over a year by our arithmetic. Rates were read on both brokers' pages on October 28, 2026.

That makes the choice simpler than most comparisons suggest. If you never borrow and trade a few times a month, pick on tools, account types and service, because commissions will not separate the two. If you use margin, or plan to, Interactive Brokers costs less at every balance Fidelity publishes.

Toolradar data: Toolradar, the software directory we run, tracks 10 investment apps as of October 27, 2026, and only 4 of them offer a free tier, per its investment apps statistics. Brokers like these two sit outside that subscription model: the account is free and the costs hide in margin, options and fund fees.

Fees side by side

The table compares what each broker publishes for a US retail account. IBKR offers two plans: Lite, with commission-free US stock trades for US residents, and Pro, which charges per share but lends and routes on better terms.

Sources, read October 28, 2026: Fidelity commissions and margin rates, IBKR stock commissions, IBKR options commissions and IBKR margin rates. Fidelity's base margin rate has been 10.825% since September 18, 2026; IBKR quotes its rates as a benchmark plus a spread.

Which is cheaper for buying index funds every month?

For a monthly ETF buyer, Fidelity and IBKR Lite are both free, and IBKR Pro is the only plan that costs anything. Take $500 a month into one broad ETF, one order each time. Fidelity and Lite charge nothing per order. IBKR Pro Fixed charges its $1.00 minimum on an order that small, which is $12 a year by our arithmetic.

The deciding costs for this investor sit elsewhere. Fidelity's own index funds trade free online, and its no-transaction-fee list covers many outside funds, but a transaction-fee fund costs $49.95 per purchase, which wrecks a $500 monthly plan. Check a fund's fee status before setting up the automatic purchase.

IBKR Lite applies Fixed pricing to some orders even on the free plan, including recurring investment instructions, OTC stocks and overnight trades. A buyer who automates purchases with IBKR's recurring tool should expect the Pro-style minimum on those orders rather than zero.

For a buy-and-hold investor, then, Fidelity is the cleaner fit. Our Fidelity vs Vanguard comparison covers the other broker most index investors weigh.

What does a 50-trade-a-month trader pay?

A trader placing 50 stock orders a month pays no commissions at Fidelity or on IBKR Lite, and $600 a year on IBKR Pro Fixed when each order is 100 shares. IBKR's own example prices 100 shares at $25 at $1.00 on Fixed, so 50 such orders cost $50 a month (our arithmetic).

Order size changes the Pro bill quickly. IBKR's example for 1,000 shares at $25 is $5.00 on Fixed, so 50 of those orders cost $250 a month, or $3,000 a year. Tiered pricing starts at $0.0035 a share with a $0.35 minimum, which cuts the 100-share order to $0.35 before exchange, clearing and regulatory fees that IBKR passes through on that plan.

So why would an active trader pay for Pro? IBKR reserves the right to reject Lite orders that look like non-retail trading, and Pro is the plan with lower margin rates and higher interest on idle cash. Fidelity keeps commissions at zero for active retail traders, but accounts it designates Professional Equity Traders pay $0.001 a share.

Options traders see almost no gap on commissions. Both brokers charge $0.65 a contract at normal volumes, so 20 contracts a month cost $13 at either before regulatory fees. IBKR Pro charges less on contracts with low premiums and above 10,000 contracts a month, which matters only to high-volume traders. Our best day trading platforms and best options trading platforms rankings cover the wider field.

If you want broker fee changes like these flagged as they happen, Finpresso sends a short daily brief at finpresso.com.

How much does margin cost at each broker?

IBKR Pro charges less than half Fidelity's margin rate at every balance Fidelity publishes. IBKR Pro starts at 5.380% for the first $100,000 and steps down above that; IBKR Lite charges 6.380% flat. Fidelity's rate depends on your debit balance and runs from 12.075% under $25,000 to 10.325% between $250,000 and $499,999.

All figures are our arithmetic: simple interest on a constant balance for one year at the rates read on October 28, 2026. Both brokers accrue interest daily and change rates with benchmark moves, so treat the table as a comparison at today's rates, not a quote. IBKR blends its tiers, so the $150,000 Pro figure charges 5.380% on the first $100,000 and 4.880% on the rest.

The gap is large enough to change behavior. A borrower carrying $50,000 at Fidelity pays about $2,600 more a year than at IBKR Pro, which is more than most investors pay in all other brokerage costs combined. Fidelity notes that special rates may be available for higher balances by phone, so a large borrower should ask before moving.

Margin adds risk as well as cost: a falling market can force sales, and Fidelity charges $32.95 when it liquidates a position to meet a margin call. Our Interactive Brokers review covers how IBKR's margin and risk rules work in more detail.

Account fees and other costs

Neither broker asks for an account minimum, and neither lists a maintenance fee, so an idle account costs nothing to keep open at either. The smaller fees are where the two part ways, and they matter mostly to investors who hold foreign shares or move money abroad.

Fidelity lists no charge for transfers of assets, domestic wires or its debit card, and charges a $50 foreign settlement fee on foreign ordinary shares that are not DTC eligible. Converting USD for a foreign-currency wire costs up to 3% of principal.

IBKR pays interest on idle cash under its own rules: Pro pays the benchmark minus 0.5% and Lite the benchmark minus 1.5%, and accounts under $100,000 in net asset value receive a proportionally lower rate. For an investor with a large cash buffer that can matter, though the size rule shrinks it for most small accounts.

Fidelity's edge is the rest of the household: IRAs, 401(k) rollovers, cash management and bill pay sit in the same login, which matters more to most families than a margin rate they never use. Our Schwab vs Fidelity and Fidelity vs Robinhood pages compare Fidelity with its other common rivals, and brokerage fees 2026 lists the wider market.

Which should you choose?

• Index and retirement investors: Fidelity. Trades are free, its own funds trade free online, and you get one place for IRAs and cash.
• Frequent stock traders who never borrow: Fidelity or IBKR Lite. Both charge nothing per trade; pick on platform and order routing.
• Margin borrowers: IBKR Pro. At $50,000 it saves about $2,600 a year over Fidelity at current rates, by our arithmetic.
• High-volume or international traders: IBKR Pro, whose per-share and per-contract tiers fall with volume and which lets you fund the account in up to 29 currencies.

For more brokers ranked by cost and features, see our best investing apps and the Charles Schwab review.

How we compared

We read Fidelity's commissions and margin rates page and Interactive Brokers' stock commissions, options commissions and margin rate pages on October 28, 2026, using the US retail account terms each publishes. Every scenario cost on this page is our arithmetic on those published rates, with the assumptions stated next to it. We did not open accounts or place trades, and we left out pass-through regulatory and exchange fees where a broker does not print a fixed amount.

FAQ

Is Interactive Brokers cheaper than Fidelity?

For margin, yes: IBKR Pro charges 5.380% on the first $100,000 and Lite 6.380%, against Fidelity's 10.325% to 12.075% depending on the balance, read October 28, 2026. For online US stock and ETF trades, Fidelity and IBKR Lite are both $0, while IBKR Pro charges per share.

Is IBKR Lite really free?

IBKR Lite charges $0 commission on US exchange-listed stocks and ETFs for US residents. Orders for OTC stocks, overnight trading and recurring investments fall under Fixed pricing instead, and IBKR can reject Lite orders that look like non-retail trading.

What is Fidelity's margin rate in 2026?

Fidelity's base margin rate has been 10.825% since September 18, 2026. Actual rates run from 12.075% for debit balances under $25,000 down to 10.325% for $250,000 to $499,999, with special rates available for larger balances by phone.

Which is better for options, Interactive Brokers or Fidelity?

They charge the same $0.65 per contract at normal volumes. IBKR Pro charges less on low-premium contracts and above 10,000 contracts a month, and both add regulatory fees. For most options traders, platform and margin terms matter more than the commission.

Which is better for beginners?

Fidelity, for most beginners: online stock and ETF trades are free, there is no account minimum, and the account sits next to retirement and cash accounts. IBKR suits beginners who plan to trade internationally or borrow on margin.

How much does it cost to borrow $50,000 on margin?

At October 28, 2026 rates, a $50,000 loan held for a year costs about $2,690 in interest at IBKR Pro, $3,190 at IBKR Lite and $5,312.50 at Fidelity, by our arithmetic on simple interest. Rates move with benchmarks, so check before borrowing.

This page is general information, not personalized financial advice; confirm current terms with Interactive Brokers and Fidelity before you open an account or borrow on margin.

Cite this: Finpresso, "Interactive Brokers vs Fidelity 2026: Fees and Margin Rates Compared", November 2026.

Finpresso publishes one daily brief on AI and finance. Join at finpresso.com.

Some offers on this page may be paid placements or contain affiliate links.