Rates Derivatives

STIR Future

Also known as: SOFR futures, Euribor futures, Short-term interest rate futures

Exchange-traded bets on short-term rates — the deepest, fastest market for central-bank expectations.

Asset class
Rates derivatives
Instrument type
Cash-settled future
Traded
Exchange (CME, ICE)
Typical users
Macro funds, banks, prop traders
P&L linear in the realised short-term rate: price = 100 − rate, so falling rates lift the price.
F₀Long futureUnderlying price at expiryProfit / loss
BeginnerWhat is it, really?

STIR (short-term interest rate) futures let you trade where money-market rates will be months or years from now. The main contracts settle on realised overnight rates — three-month compounded SOFR in the US, plus Euribor in Europe.

The quoting trick everyone learns first: the price is 100 minus the interest rate. A future at 96.50 implies a 3.5% rate. If you think rates will be cut more than the market expects, you buy (rates down → price up).

These are among the most heavily traded instruments in existence — the arena where every inflation print, payrolls number and central-bank speech is instantly converted into price. When headlines say "markets moved to price three cuts", this is the market that moved.

Key intuition: a STIR future is a tradable pixel of the future path of policy rates. The strip of contracts, laid end to end, is the market's rate forecast.
IntermediateHow it works in practice

Contract mechanics (3-month SOFR)

  • Settlement: 100 − (annualised compounded SOFR over the contract's 3-month reference quarter) — purely backward-looking, no fixing risk.
  • Size: $25 per basis point per contract; ticks of ¼ or ½ bp.
  • Listings: quarterly (Mar/Jun/Sep/Dec) years out, plus 1-month contracts for meeting-level precision.

Trading the strip

  • Outrights: a view on one quarter's average rate.
  • Calendar spreads: buy one contract, sell another — a bet on the pace of hikes/cuts between two quarters, with less outright risk.
  • Butterflies/condors: curvature trades on the path's shape.
  • Options on STIR futures: the liquid way to trade probabilities of specific policy scenarios (huge open interest builds at strikes matching "policy lands at X%").

Relation to OIS

A SOFR future and a matching-period OIS express the same expectation; differences are convexity (futures margining) and microstructure. Curve builders use futures for the front 2–3 years, swaps beyond.

Worked example: the Dec contract trades at 96.00 (4.0%). You expect faster cuts averaging 3.5% that quarter → buy. Right: contract settles 96.50, +50bp × $25 = $1,250 per contract. A 100-lot: $125k. Wrong by the same amount: −$125k.
AdvancedPricing & valuation

From prices to policy paths

Each quarterly settlement is \(100 - \bar{r}_q\) where \(\bar{r}_q\) compounds daily SOFR. With meeting dates inside the quarter, assume piecewise-constant policy and solve the strip for per-meeting expected moves — the futures-implied policy path. Options on the contracts add full distributions: risk-neutral densities via Breeden–Litzenberger on the strike ladder.

Convexity adjustment

Daily margining pays the long when prices rise (rates fall) — cash arrives in low-rate states, a systematic benefit priced into futures. Futures-implied forward rates therefore exceed OIS forwards:

$$ f_{fut} - f_{OIS} \;\approx\; \tfrac{1}{2}\,\sigma^2\, T_1 T_2 \quad \text{(Ho–Lee approximation)} $$

growing with maturity² and vol² — negligible in the whites (first year), tens of basis points in the golds (4–5 years). Curve construction must strip it; getting it wrong misprices the whole back strip.

Microstructure edge cases

Since settlement compounds realised rates, the front contract's remaining uncertainty decays daily — after the last meeting in its window it becomes nearly deterministic. Turn-of-quarter repo spikes, IORB tweaks, and debt-ceiling distortions all print directly into settlements; traders model the SOFR-vs-target-rate spread explicitly.

Practitioner note: read the futures strip before every macro discussion — it's the consensus you're implicitly trading against. Your view only matters where it differs from what's already at 96.50.