Bybit Switches to Single-Counted Open Interest on June 11

Bybit will change how it reports open interest from 11 June 2026, moving from bilateral (dual-counted) to unilateral (single-counted) measurement. The shift will cut displayed OI figures by roughly half — but Bybit stresses that this reflects a change in calculation methodology only, with traders’ actual positions, margin, risk exposure and position limits all unaffected.

What is changing

Open interest measures the total number of derivatives contracts that remain open and unsettled. The question of how to count it has long divided the industry: every contract has a long side and a short side, so a venue can either count both sides (bilateral) or count the position once (unilateral).

Bybit currently uses bilateral counting. When a trader holds matching long and short positions for the same amount, bilateral measurement counts both sides separately. Under the new unilateral methodology, the same position is counted only once. Because the underlying market activity is identical and only the counting changes, the displayed OI figure is expected to drop by approximately 50%.

The exchange frames the move as a transparency and comparability upgrade. Single-counted OI is the convention used across much of the global derivatives market and by most third-party data aggregators, so the change gives traders and analysts a more directly comparable view of Bybit’s positioning against other venues — and removes the distortion that dual-counting introduces when stacking Bybit’s raw figures against single-counted competitors.

Why positions and limits don’t change

The critical point for traders is that nothing about their actual risk changes. Position limits on Bybit are calculated as OI multiplied by a rate. Because unilateral OI becomes approximately 50% of the previous bilateral value, Bybit will double the applicable rate for each contract — leaving every trader’s actual position limit exactly where it was. Margin requirements, profit and loss calculations and risk exposure are likewise untouched.

In other words, the change is presentational at the level of headline OI figures and self-correcting at the level of the limits that depend on them. A trader who does not look at aggregate OI charts may not notice the change at all, beyond the lower numbers displayed on market data pages.

Platform and API updates

From 11 June 2026, the updated OI displays will appear across Bybit’s Markets page (OI charts for Perpetuals, Futures and Options), the Trading page OI indicator, the Contract detail and Open Interest pages, and the in-app candle lines and data panel.

For developers and institutional users accessing OI data via API, Bybit is adding two new fields: singleOpenInterest, the unilateral open interest value, and singleOpenInterestValue, the unilateral open interest expressed in USD. API users and platform integrators should update their systems before the effective date to avoid misreading the new figures or double-handling the methodology change in downstream analytics.

Context: standardising crypto derivatives data

The change is part of a broader, slow-moving push toward standardised reporting in crypto derivatives — a market that has historically suffered from inconsistent definitions of volume, open interest and liquidity across venues. Inconsistent OI counting has been a persistent source of confusion for analysts comparing exchanges, since a dual-counted venue can appear to carry twice the open interest of a single-counted competitor with identical real positioning.

By moving to the more widely adopted single-counted convention, Bybit removes one such inconsistency for the world’s second-largest crypto exchange by volume. The timing also aligns with rising institutional scrutiny of crypto market data quality, as more traditional finance participants — who are accustomed to the standardised OI reporting of regulated futures markets like CME — enter the digital asset derivatives space and expect comparable data conventions.

FAQ

What is Bybit changing about open interest reporting?
Effective 11 June 2026, Bybit is moving from bilateral (dual-counted) to unilateral (single-counted) open interest measurement. Under the new method, a position is counted once rather than counting both its long and short sides separately, which will cause displayed OI figures to drop by approximately 50%.

Will this affect my positions or margin?
No. Traders’ actual positions, position limits, margin requirements, profit and loss calculations and risk exposure all remain unchanged. Because position limits are calculated as OI multiplied by a rate, Bybit will double the per-contract rate to offset the roughly 50% reduction in displayed OI, keeping actual position limits the same.

What do API users need to do?
Bybit is adding two new API fields — singleOpenInterest (unilateral OI value) and singleOpenInterestValue (unilateral OI in USD). Developers and institutional users accessing OI data via API, as well as platform integrators, should update their systems before the 11 June 2026 effective date to handle the new methodology correctly.

Although the change will make Bybit’s headline open interest figures appear smaller overnight, the practical effect is greater comparability and cleaner data — a net positive for traders and analysts who track positioning across multiple venues. As crypto derivatives markets mature and institutional participation grows, moves toward standardised, single-counted reporting are likely to become the norm rather than the exception across the sector.