UnlockInstitutional-GradeLiquidity.
Execute SPX box spreads directly in your existing brokerage account to access low-cost, risk-defined funding. Built for U.S. households with invested portfolios, not just ultra-wealthy investors.
Annual Rate Savings
Per $100,000 borrowed
224bps
$2,237 / year
* Broker margin rates reflect the average among major U.S. brokers.
Loan Savings Calculator
Adjust your portfolio size and funding need to estimate how much broker margin may be draining each year and how much a market-based structure could preserve.
Model Inputs
Capital Utilization Ratio
Percentage of your total portfolio buying power used as margin for this loan.
8.0%
Funding Source Comparison
Comprehensive analysis of available funding mechanisms ranked by implied rate and capital efficiency.
Research, Policy & Execution Notes
Structured analysis of financing markets, tax treatment, and governance controls for disciplined portfolio decisions.
Broker Margin vs. SBLOC vs. Box Spread
A clear side-by-side look at cost, flexibility, and risk across the three main portfolio-liquidity paths.
How a Box Spread Works in a Real Portfolio
A practical scenario showing how cash, NLV, and account risk change after a $200,000 box spread withdrawal.
Why We Use SPX for Box Spreads
A practical explanation of why European-style SPX options usually produce a cleaner funding structure than many other underlyings.
Section 1256 and the 60/40 Rule
A concrete tax example showing how a bank loan and an SPX box spread can produce different after-tax funding outcomes.
US Liquidity Monitor
Market context for funding cost, risk regime, and spread behavior.
| Metric | Current | 7D Change |
|---|---|---|
SOFR | 3.65% | -2 bps |
UST 3M | 3.7% | -1 bp |
UST 10Y | 4.2% | +3 bps |
SPX | 6,699.37 | +0.29% |
VIX | 23.52 | -0.8 pts |
SPX Box Spread | 4.01% | -1 bp |
How to read this snapshot
- SOFR and UST changes directly shift the reference floor for box spread implied rates. A declining SOFR typically compresses funding cost.
- Elevated VIX widens option execution spreads, increasing slippage in box construction. Monitor for regime shifts above 20.
- Box-SOFR Spread is the key alpha metric. Persistent negative spread confirms box funding advantage over interbank rates.