Measured,
not promised.

How these numbers are produced

NBBO at submit. At the moment Bridge submits an order to a follower's broker, our licensed real-time options NBBO feed records the best national bid and best national ask for that contract. The midpoint of that bid–ask is the reference price for every fill below. This is the price you would expect to receive in a perfectly liquid, zero-latency fill.

Slippage = filled price minus NBBO mid, signed for direction. For a buy order, slippage is positive when you paid above the mid (worse than ideal) and negative when you paid below it (better than ideal). For a sell, the sign is reversed: positive = received below mid. A fill exactly at mid = 0¢ slippage. The sign convention matches the broker's economic outcome for the follower.

Real fills only. Only dispatches where the broker confirmed a fill (filled_qty > 0) and an NBBO snapshot was captured at submit (slippage_vs_nbbo_cents IS NOT NULL) are counted. Provisional orders, rejected orders, risk-blocked dispatches, and unfilled attempts are never included in any number on this page.

Immutable source rows. Once a dispatch row is written, the NBBO snapshot and fill price are never revised. These numbers are computed from the same append-only audit rows that our internal risk and compliance logs reference.

Minimum sample threshold. If fewer than 25 qualifying fills exist in the trailing 30-day window, this page shows "not enough fills yet" rather than displaying a number based on thin data. We will never show a figure that could mislead due to a small sample.

Refresh cadence. Stats are recomputed from the live database every 10 minutes. The timestamp shown is when this batch was computed.

What is NBBO?

The National Best Bid and Offer (NBBO) is the highest bid and lowest ask for a security across all registered exchanges at a given moment, as required to be displayed under SEC Rule 15c3-5. For options, NBBO covers all U.S. options exchanges. The midpoint is the arithmetic mean of the best bid and best ask. It is the standard reference price used in TCA (Transaction Cost Analysis) and is what institutional desks use to measure execution quality.

Source

NBBO snapshots come from our licensed real-time options NBBO feed, captured at the moment the order is submitted to the broker API, not at the moment the fill arrives. Broker fill prices come from broker order confirmations via the OAuth-connected brokerage API. No estimates or reconstructed quotes are used.

What this data doesn't tell you

• Slippage vs mid ≠ P&L. A fill at or inside the NBBO mid on a wide bid–ask spread still means you paid a real spread cost. This metric measures execution quality against the mid — it does not measure whether the trade was profitable, nor does it account for bid–ask width.
• Per-contract price, not per-dollar. Slippage is measured in cents per contract. A 1¢ slip on a $0.10 option is 10% of premium; on a $5.00 option it is 0.2%. Context matters; this page shows the raw cent figure only.
• Sample = followers' brokers. The broker distribution reflects which brokers Bridge followers actually use, which may not match your broker or fill environment. Per-broker rows show exactly which accounts contribute each figure.
• Quote latency window. The NBBO is captured at order submission. If the market moved between submission and fill (typical for limit orders that rest), the resulting slippage includes that market movement, not just execution quality. Market orders and immediately-filled limit orders are cleanest; resting limit orders may show wider apparent slippage due to price drift.
• Not forward-looking. Historical fill quality does not guarantee future execution. Liquidity, spread width, and market conditions vary. Unusual volatility events may produce outliers that are visible in the p95 column.