Daily BTC options market report · 24-hour comparison

Bitcoin options add six-month convexity as front-end volatility rises

The six-month BF25 increase stood out as Bitcoin’s most notable surface move, while the front end moved higher.

02 · Options market read

What the volatility surface did.

5 of 6 headline tenors were comparable at both endpoints. The largest ATM IV move was 1W at +2.36 volatility points, to 36.83%.

Derived directly from structured Derivasys surface data

03 · Catalyst check

05 Sept 2026, 16:59 UTC to 06 Sept 2026, 16:59 UTC

News context unavailable.

News context unavailable because source coverage was incomplete.

04 · Detailed analysis

What changed across the BTC volatility surface.

Implied versus realised

At the 16:59 UTC cutoff, 1W ATM IV was 36.83%, broadly in line with seven-day realised volatility of 36.36%; 24-hour realised volatility was 18.76% and 30-day realised volatility was 37.53%.

Front end

Front-end ATM IV increased, averaging +1.28 volatility points to 37.24% across 1W, 2W and 1M.

Long end

Six-month ATM IV was broadly unchanged at 40.13% (-0.07 volatility points); 1Y was unavailable.

Skew

RR25 was broadly unchanged, averaging -0.05 volatility points to 0.68% across the five available headline tenors.

Convexity

BF25 was broadly unchanged, averaging +0.01 volatility points to 2.20% across the five available headline tenors.

Largest standard-tenor move

The largest standard-tenor ATM IV move was +2.36 volatility points at 1W, to 36.83%.

Universe roll: added 10SEP26; removed 6SEP26. Comparisons use common expiries only.

05 · Standard-tenor ranking

Largest surface events

01

Largest standard-tenor ATM IV move

1W, +2.36 vol pts
02

Largest eligible smile rotation

9SEP26, -1.18 vol pts
03

Largest eligible SVI sigma move

27NOV26, +0.1988 param
04

Largest standard-tenor RR25 move

3M, -0.12 vol pts
05

Largest standard-tenor BF25 move

6M, +0.12 vol pts
06

Largest eligible SVI rho move

25DEC26, +0.0994 param

06 · ATM volatility

Standard-tenor ATM implied volatility.

TenorCurrent (vol %)Previous (vol %)Change (vol pts)Relative change
1W36.8334.47+2.36 vol pts+6.85%
2W37.4636.52+0.94 vol pts+2.57%
1M37.4236.89+0.53 vol pts+1.44%
3M38.8838.87+0.01 vol pts+0.03%
6M40.1340.20-0.07 vol pts-0.17%
9M41.4641.40+0.06 vol pts+0.14%
1YUnavailableUnavailableUnavailableUnavailable

07 · Risk reversals

RR25 skew moved most at 3M.

RR25 was broadly unchanged, averaging -0.05 volatility points to 0.68% across the five available headline tenors. Negative RR25 denotes a richer 25-delta put wing under the call-minus-put convention.

-0.3%0.2%0.6%1.1%1.5%1W2W1M3M6M9M
TenorCurrent (vol %)Previous (vol %)Change (vol pts)
1W1.201.28-0.08 vol pts
2W1.251.31-0.06 vol pts
1M1.040.96+0.08 vol pts
3M-0.050.07-0.12 vol pts
6M-0.060.00-0.06 vol pts
9M0.240.12+0.12 vol pts
1YUnavailableUnavailableUnavailable

08 · Butterflies

BF25 convexity changed most at 6M.

BF25 was broadly unchanged, averaging +0.01 volatility points to 2.20% across the five available headline tenors. BF25 measures the average 25-delta wing premium over ATM IV.

1.6%2.0%2.3%2.7%3.0%1W2W1M3M6M9M
TenorCurrent (vol %)Previous (vol %)Change (vol pts)
1W1.821.86-0.04 vol pts
2W1.851.87-0.02 vol pts
1M2.182.22-0.04 vol pts
3M2.452.43+0.02 vol pts
6M2.682.56+0.12 vol pts
9M2.802.800.00 vol pts
1YUnavailableUnavailableUnavailable

09 · Expiry effects

Near-settlement moves, shown with context.

Contracts with fewer than 2 full days to expiry remain in the tables but are excluded from headline rankings. Settlement proximity, time decay, changing liquidity and fewer quotes can exaggerate their changes.

0.6d

ATM IV change

7SEP26, +3.61 vol pts
1.6d

ATM IV change

8SEP26, +3.50 vol pts

10 · Volatility term structure

Today against the previous 24-hour snapshot.

Only fixed tenors bracketed by listed expiries at both snapshots are charted. The listed-expiry table preserves the observable exchange maturities underneath those interpolated points.

33.6%35.8%38.0%40.1%42.3%1W2W1M3M6M9M

Suppressed outside the observable listed-expiry range: 1Y.

ExpiryTime leftForward now (USD)Forward change (USD)ATM IV nowATM IV changeRR25 changeBF25 change
7SEP26Expiry effect0.6 days79,664.42-436.82 USD28.50%+3.61 vol pts+0.33 vol pts-0.25 vol pts
8SEP26Expiry effect1.6 days79,653.01-444.36 USD30.60%+3.50 vol pts+0.05 vol pts+0.05 vol pts
9SEP262.6 days79,674.93-431.03 USD32.48%+1.80 vol pts-0.46 vol pts+0.20 vol pts
11SEP264.6 days79,682.01-431.24 USD35.71%+2.48 vol pts-0.09 vol pts-0.03 vol pts
18SEP2611.6 days79,746.37-419.57 USD37.67%+1.04 vol pts-0.13 vol pts-0.01 vol pts
25SEP2618.6 days79,790.78-421.73 USD37.20%+0.98 vol pts+0.14 vol pts-0.12 vol pts
30OCT2653.6 days80,134.29-414.63 USD37.57%+0.12 vol pts+0.06 vol pts+0.02 vol pts
27NOV2681.6 days80,450.41-424.89 USD38.73%+0.04 vol pts+0.13 vol pts-0.07 vol pts
25DEC26109.6 days80,767.18-433.60 USD39.10%-0.08 vol pts-0.47 vol pts+0.13 vol pts
26MAR27200.6 days81,696.89-436.33 USD40.27%-0.08 vol pts-0.02 vol pts+0.12 vol pts
25JUN27291.6 days82,628.93-436.92 USD41.67%+0.07 vol pts+0.15 vol pts-0.03 vol pts

11 · Smile movement

Reconstructed SVI smiles for every common expiry.

Each overlay uses the stored five-parameter SVI fit and the snapshot-specific time to expiry. Ultra-short expiries are displayed but do not determine the headline ranking.

7SEP26rotation towards calls · wing steepening
-0.30k0.00k+0.30k
8SEP26wing steepening
-0.30k0.00k+0.30k
9SEP26rotation towards puts · wing steepening
-0.30k0.00k+0.30k
11SEP26parallel shift higher · wing steepening
-0.30k0.00k+0.30k
18SEP26parallel shift higher
-0.30k0.00k+0.30k
25SEP26parallel shift higher
-0.30k0.00k+0.30k
30OCT26parallel shift higher
-0.30k0.00k+0.30k
27NOV26limited movement
-0.30k0.00k+0.30k
25DEC26limited movement
-0.30k0.00k+0.30k
26MAR27parallel shift lower
-0.30k0.00k+0.30k
25JUN27limited movement
-0.30k0.00k+0.30k

Surface movement heatmap

Each cell is the fitted IV change in volatility points. Rows are listed expiries; columns run from the put wing through ATM to the call wing.

12 · Technical appendix

Model parameters and normalized Greeks.

These diagnostics preserve the fitted-surface audit trail without competing with the main market story.

Show SVI parameter changes and normalized Greeks

SVI diagnostics

Daily movement in a, b, rho, m and sigma.

Among ranking-eligible expiries, the largest absolute rho change occurred at 25DEC26; the largest sigma change occurred at 27NOV26.

ExpiryΔ aΔ bΔ rhoΔ mΔ sigmaSmile classification
7SEP26+0.00850-0.02350+0.02660+0.00950+0.02950rotation towards calls, wing steepening
8SEP26-0.00440+0.00080-0.02410-0.00950+0.04180wing steepening
9SEP26-0.00310+0.00730+0.04740+0.02810-0.00730rotation towards puts, wing steepening
11SEP26-0.01550+0.01000+0.02770+0.00420+0.08970parallel shift higher, wing steepening
18SEP26-0.02130+0.01710-0.00700-0.02450+0.08910parallel shift higher
25SEP26-0.02540+0.02150-0.02970-0.04940+0.11290parallel shift higher
30OCT26-0.01370+0.01220+0.02580-0.00460+0.05100parallel shift higher
27NOV26-0.07880+0.05450+0.01760-0.07090+0.19880limited movement
25DEC26-0.06230+0.02290+0.09940+0.07880+0.12590limited movement
26MAR27-0.06480+0.02500+0.08250+0.06180+0.11170parallel shift lower
25JUN27-0.05940+0.02800-0.01480-0.04520+0.09400limited movement

Current surface characteristics

Where normalized model Greek intensity is highest.

These are comparable Black-forward Greeks for a one-BTC ATM-forward call at each listed expiry—not portfolio exposure, open interest or a prediction of dealer positioning.

Highest Vega25JUN27, 289.585815 USD / vol pt
Highest Gamma7SEP26, 0.000424 1 / USD
Highest Theta Decay7SEP26, -299.676169 USD / day
Highest Vanna25JUN27, 0.001752 delta / vol pt
Highest Volga25JUN27, -24.103146 USD / vol pt²

Completed-session cross-asset context

Crypto volatility against US equity risk.

BTC 30-day implied volatility was 2.5 times VIX, while its 30-session return correlation with SPX was low at 0.16.

Implied-volatility premium

BTC 30-day ATM IV was 36.20%, against VIX at 14.53: a 21.67-point spread and 2.49× ratio.

Realised-volatility regime

BTC 20-calendar-day realised volatility was 50.32%, versus SPX 20-session realised volatility of 8.30%. The spread ranked at 87.7 percentile of 228 prior observations.

Equity co-movement

Return correlation with SPX was 0.158 over 30 aligned sessions and 0.352 over 60 sessions. VIX9D, VIX and VIX3M closed at 11.97, 14.53 and 17.61.

As of 04 Sept 2026, 20:00 UTC. market-context-v1; crypto RV is 20 calendar-day close-to-close log returns annualised with sqrt(365); SPX RV is 20 US-session log returns annualised with sqrt(252).

13 · Methodology and provenance

Generated from measured Derivasys surface data.

Current snapshot
06 Sept 2026, 16:59 UTC
Comparison snapshot
05 Sept 2026, 16:59 UTC
Source
Derivasys proprietary historical SVI surface and canonical BTC index databases
Realised volatility
Annualised root-mean-square of one-minute canonical BTC-USD index log returns using a 365-day basis; all windows end at the current snapshot.
Comparison window
Nearest successful surface snapshots approximately 24 hours apart
RR convention
25-delta call IV minus 25-delta put IV
BF convention
Average 25-delta wing IV minus ATM forward IV
Fixed tenors
Fixed-tenor measures are published only when listed expiries bracket the target at both comparison snapshots. Targets outside either observable range are suppressed, not extrapolated; headline rankings use only supported tenors.
Smile reconstruction
Listed-expiry smiles are reconstructed from stored SVI total-variance parameters on a fixed log-moneyness grid.
Ultra-short expiries
Expiries with fewer than 2 full days remaining stay in detailed tables but are excluded from headline rankings. Settlement proximity, time decay, changing liquidity and fewer quotes can exaggerate their changes.
Greek normalization
Black forward Greeks for a normalized one-BTC ATM-forward call, zero rate, fitted SVI IV
Catalyst policy
Only sufficiently relevant, reliably sourced events are shown; otherwise no catalyst is assigned.
Bitcoin options add six-month convexity as front-end volatility rises