Research
Box Spread Rates vs. SOFR
The 1-month Haven SPX Box Rate and SOFR, paired on the same day from the cleaned history.
Key takeaway
From 2018 through 2025, the 1-month Haven SPX Box Rate averaged 0.39 percentage points above SOFR on 1,836 paired days. 2020 and 2021 are included.
1-month Haven SPX Box RateSOFR
Hover a point for that year.
Yearly comparison
| Year | Days | 1-month Haven SPX Box Rate | SOFR | Haven minus SOFR, pp |
|---|---|---|---|---|
| 2018 | 165 | 2.45% | 1.97% | 0.47 |
| 2019 | 238 | 2.55% | 2.20% | 0.35 |
| 2020 | 231 | 0.93% | 0.37% | 0.56 |
| 2021 | 248 | 0.52% | 0.04% | 0.48 |
| 2022 | 244 | 2.11% | 1.64% | 0.47 |
| 2023 | 245 | 5.20% | 5.01% | 0.20 |
| 2024 | 237 | 5.44% | 5.14% | 0.30 |
| 2025 | 228 | 4.56% | 4.24% | 0.32 |
| 2026 | 170 | 4.08% | 3.65% | 0.43 |
SOFR begins in April 2018, so the table starts in 2018. 2026 runs through October 6. SOFR on October 7 was 3.88%.
What this means
SOFR is an overnight secured rate. The navy line is the 30-day Haven SPX Box Rate, so the two are not the same maturity. From 2018 through 2025 the Haven SPX Box Rate averaged 0.39 percentage points above SOFR, including 2020 and 2021.
Sources: Methodology · New York Fed SOFR. The table uses the cleaned daily history.
Haven Funding LLC is owned by Haven Systems LLC. Neither firm is a bank or a registered broker-dealer. Securities and execution services are provided through Interactive Brokers LLC. The Haven SPX Box Rate is a constant-maturity reference rate. It is not a Truth in Lending APR and not a commitment to lend.