NBP Tracks TTF Lower After French Strike Ends, Storage Gap Offers Limited Support
Britain's day-ahead gas prices have retreated from last week's 2023 highs as supply flows recover, even with European storage running well below seasonal norms.
The ICE Endex TTF front-month contract last traded at €79.54 per megawatt-hour as of Sunday (2026-09-20), according to live market data — down from the 83.40 euro peak reached on Monday (2026-09-14), which parameter.io described as the strongest level for that benchmark since 2023. Britain's NBP wholesale gas price tracked the pull-back closely: the benchmark fell 0.7% to 200.10 pence per therm on Tuesday (2026-09-15), as the tailwind from the early-September peak dissipated.2,1
Supply drove the reversal. European wholesale gas prices fell for a third consecutive session on Thursday (2026-09-10) after a strike in France's energy sector ended, with the TTF front-month contract declining 1.23% to approximately €76.98 per megawatt-hour, Yahoo Finance reported. NBP day-ahead tracked that move closely.3
The storage backdrop made the sell-off more notable. Gas Infrastructure Europe data show European underground facilities at roughly 68% of total capacity at mid-September, trailing the typical five-year average for this point in the injection season, according to parameter.io and blockonomi.com. A deficit of that scale would normally provide near-term support. Yet available supply flows proved sufficient to overwhelm that floor once the French strike disruption cleared.2,1
The rapid retreat from the 83 euro area on TTF, and the corresponding pull-back on NBP, reflects how much of the early-September rally was built on disruption risk rather than inventory fundamentals. A storage position at 68% was not tight enough to sustain prices at those levels when supply flows proved adequate.
The early September rally had drawn additional support from reported shipping disruption around the Strait of Hormuz, which raised concerns about LNG availability into Europe. Diplomatic efforts to address those concerns were under way at mid-September, parameter.io and blockonomi.com reported, though the disruption had not fully normalised.2,1
On the forward curve, NBP Q+1 last traded at €81.35 per megawatt-hour as of Sunday (2026-09-20), against a Cal+1 contract at €61.98, a spread of close to €20, according to live market data. Germany's THE M+1 contract sat at €80.70 per megawatt-hour over the same session. The near-to-far spread suggests traders treat current tightness as seasonal rather than a constraint extending into 2027.2
Both the NBP and TTF benchmarks dropped 0.7% on Tuesday (2026-09-15), illustrating how tightly British and continental European gas prices tracked through the correction from Monday (2026-09-14)'s highs, parameter.io reported.2,1
Shipping disruption in the Strait of Hormuz has not vanished from the picture. Its near-term relevance to European gas depends on whether reduced LNG availability tightens Atlantic supply enough to offset the current downward pressure from recovered French output. No named source in the packet has quantified that offset.1
What traders on the NBP day-ahead curve cannot treat as durable is the assumption that supply pressure will persist. European storage needs to close the gap with seasonal averages through the remaining weeks of the injection season. If injection rates disappoint — from reduced supply flows, an early cold snap, or renewed disruption in European transit routes — the market enters the heating draw with thinner inventory cover than recent comparable years.
The weekly Gas Infrastructure Europe storage fill rate is the number to track over the next fortnight. If European inventories show progress toward historical seasonal norms, the near-term premium embedded in NBP Q+1 will face further selling pressure. If fill rates stall and storage remains near 68% into October, the roughly €20 per megawatt-hour spread between NBP Q+1 and Cal+1 is likely to narrow, with short positions in NBP day-ahead exposed to any reversal.2