Bitcoin has risen 7.33 percent in September, putting it on the verge of setting an all-time high September return.

Blockchain outlet Decrypt reported on Sept. 29 that if the current gain holds, bitcoin would surpass September 2024's 7.29 percent and post its strongest September return since 2013.

Confirmation of the record hinges on the Sept. 30 close. Bitcoin is hovering around $83,600, the level that will determine whether it maintains the best September return.

September has long been a weak month for bitcoin. CoinGlass data show bitcoin finished lower in 8 of 13 Septembers from 2013 to 2025. It fell for 6 straight years from 2017 to 2022. Even including this year's gains, the average September return is minus 2.34 percent, the lowest among months.

Recent performance has differed. Bitcoin ended September 2023 up 3.91 percent, September 2024 up 7.29 percent and September 2025 up 5.16 percent. If it ends positive this year, it would mark 4 consecutive Septembers of gains.

Sentiment was not optimistic earlier this month. After a 25 percent jump in August, bitcoin started September at around $78,500. When the U.S. Senate's Clarity bill failed in a 49 to 50 vote on Sept. 15, $450.4 million flowed out of spot bitcoin exchange-traded funds. It was the biggest daily outflow since June.

A day later, the U.S. Federal Reserve raised its policy rate by 25 basis points to 3.75 to 4 percent. It was the first hike since 2023 and weighed on risk assets that are sensitive to rates. Bitcoin slid to around $75,000 after the hike, suggesting a repeat of September weakness.

The reversal came from ETF flows. Spot bitcoin ETFs later saw inflows of about $2.98 billion for 7 straight sessions. Nearly $1 billion came in on Sept. 21 alone, the strongest daily inflow since October 2025. Combined with the liquidation of more than $800 million in short positions over 24 hours, bitcoin rose as high as $87,354, its highest since late January.

Bitcoin later gave back about 4 percent of its gains. On Sept. 29 it slipped to around $83,000, and pressure grew after Brent crude climbed back above $100 a barrel following U.S. President Donald Trump's rejection of Iran's proposal to reopen the Strait of Hormuz.

Technical indicators still lean to the upside. The average directional index stood at 42.3, above 25, a benchmark for a strong trend. The relative strength index was at 61.2, below the 70 level seen as overheating. A so-called golden cross, with the 50-day moving average above the 200-day moving average, also remains in place. If $82,626 breaks, the next support zone was presented as between $81,166 and $79,705.

This September rebound has not fully recovered annual performance. Bitcoin is still 4.4 percent below about $87,497, its trading price at the start of the year. Last year also saw a 3.69 percent fall in October after a September gain, and a 23 percent drop over the whole fourth quarter.

In this situation, markets are also watching the next monetary policy schedule. The Fed's next meeting is set for Oct. 27-28, followed by a meeting on Dec. 8-9. Bitcoin's average October return so far is 19.92 percent, but such performance cannot be taken for granted this year. Ultimately, this record is closer to a gauge of whether September's seasonal weakness is fading than a simple monthly rebound.