How Our Margin Calculator Works
Enter your margin loan amount and borrowing period to see how much interest you would pay across different brokerages. The calculator compares Public’s lowest margin rates with other leading US brokers to show potential savings in real dollars. Lower rates and smaller estimated interest costs mean you keep more money invested and compounding.
The calculation:
Annual Interest Cost = Margin Loan Amount × Annual Margin Rate
Interest accrues daily and compounds using a 360-day convention:
- Daily Rate = Annual Margin Rate ÷ 360
- Daily Interest = Margin Balance × Daily Rate × (1 + Daily Rate)^days
Interest compounds daily over 365 calendar days, meaning you pay interest on accumulated interest.
How Much Can You Save with the Public’s Lower Margin Rates?
When you borrow on margin, even small differences in interest rates translate to significant annual savings. A 1% difference on a $50,000 margin loan means over $500 saved every year – money that stays in your portfolio instead of going to interest payments.
Public offers a 5.15% base margin rate, with tiered rates as low as 4.20% for larger margin balances. Compared with brokers charging more than 12% on smaller balances, the difference can add up quickly.
On a $10,000 margin loan held for 365 days:
Public (5.15%): $535.99/year
Broker at 12.08%: $1,302.14/year
Estimated annual savings: $766.15
On a $100,000 margin loan held for 365 days:
Public (5.00% tiered rate): $5,199.77/year
Broker at 10.57%: $11,316.02 /year
Estimated annual savings: $6,116.25
Lower borrowing costs can leave more capital available in your portfolio. If those savings remain invested, they may also have the opportunity to compound over time.
Margin Interest Rates Compared: Base Tier Across Leading Brokers
Here is how Public base margin rate stacks up against other major US brokerages:
The difference is dramatic:
On a $10,000 margin loan held for one year:
- Public (5.15%): $535.99 in interest
- Traditional broker average (~12.08%): $1,302.14 in interest
- Your savings with Public: $766.15
Even for smaller margin balances, Public’s 5.15% base rate remains close to other low-cost brokerage offerings and significantly below several traditional brokers with base margin rates above 12%.
Why Margin Rate Differences Add Up
The gap between high and low margin rates creates a cascading effect on your investment returns, especially for active traders or those maintaining longer-term margin positions.
The compound impact:
Money saved on margin interest can be reinvested, potentially compounding your returns over time. Consider a trader maintaining an average $50,000 margin balance:
- At 10.63%: $5,686.22 estimated annual interest cost
- At 5.15% with Public: $2,679.93 estimated annual interest cost
- Estimated annual savings: $3,006.29
If the same balance and rates remained unchanged, that would equal approximately $15,031.45 in interest savings over five years, before accounting for any potential investment growth on the money saved.
Additional benefits of lower rates:
- Strategy flexibility: Lower costs make certain margin strategies more viable and profitable
- Risk buffer: Reduced interest expenses provide more cushion during market volatility
- Faster position recovery: Less interest drag means positions can recover profitability more quickly
For traders using margin regularly, rate differences aren’t just line items—they’re a significant factor in overall portfolio performance.
Public’s Competitive Margin Rate Advantage
Public offers some of the most competitive margin rates among leading US brokerages, with a transparent tiered structure that rewards larger account balances.
Why Public rates stand out:
Traditional brokers often charge 10-12% for smaller accounts, with rates that decrease slowly and only for very large balances. Public competitive base rate means even newer margin traders benefit from institutional-level pricing. Unlike brokers that reserve low rates only for multi-million dollar accounts, Public tiered structure makes competitive rates accessible at achievable balance levels.
Public’s approach combines competitive rates with a trading experience built for today’s investors—not legacy infrastructure with legacy pricing.
Getting Started with Margin Trading on Public.com
Application Process:
- Go to Settings → Margin Account
- Complete the quick application
- Get approval notification (usually instant)
- Start trading on Public with increased buying power
Key Benefits:
- Industry-leading rates: 5.15% base rate, tiered down to 4.20% for larger balances
- Advanced options strategies: Access Level 3+ options like spreads and iron condors
- No commission: $0 commission stock and ETF trades
- Real-time monitoring: Track margin usage and buying power instantly
Ready to start saving on margin costs? Apply for margin trading on Public.com and start taking advantage of our competitive rates and trading features.
