September is Bitcoin's worst month

Bitcoin has lost money in eight of the last 13 Septembers, with an average monthly loss of 2.9%, the worst of any calendar month. Traders call it Red September.

“Bitcoin (CRYPTO:BTC) has lost money in eight of the 13 Septembers since 2013, and its average monthly return is a loss of about 2.9%, the worst of any month on the calendar”

But that curse is breaking

Bitcoin has closed higher in each of the last three Septembers, gaining 3.9% in 2023, 7.3% in 2024, and 5.2% in 2025. This year's 3.4% gain continues a four-year winning streak.

“Bitcoin has closed higher in each of the last three Septembers. It gained 3.9% in 2023, 7.3% in 2024, and 5.2% in 2025”

Bitcoin started August at $78,563

Bitcoin closed August at $78,563 and trades at $81,214 as of September 19, 2026, up about 3.4% so far this month despite turbulent trading.

Senate rejected crypto bill on September 15

The Senate voted 49-50 against advancing the CLARITY Act on September 15, which would have set federal rules for the crypto market. Bitcoin dipped to around $76,000 after the vote.

“On September 15, the Senate voted 49-50 against advancing the CLARITY Act, the bill that would have set federal rules for the crypto market.”

Fed raised rates on September 16

The Federal Reserve raised rates to 3.75% to 4.00% on September 16, its first hike since 2023. Bitcoin dropped to about $76,000 and held there.

“The Fed raised rates to a range of 3.75% to 4.00%, its first hike since 2023, and Bitcoin dropped to about $76,000”

Massive ETF outflows hit on September 15

Investors pulled $450 million from spot Bitcoin ETFs on September 15 alone, the largest single-day withdrawal since June 25. This came after $3.8 billion in inflows over the three weeks to September 5.

“Investors pulled $450 million from spot Bitcoin ETFs on September 15 alone, the largest single-day withdrawal since June 25”

Bitcoin rebounded from $76,400 to $81,702

Bitcoin climbed from $76,400 on September 17 to $81,702 on September 18. Most of the rebound came from short sellers being forced to buy back as $300 million in leveraged positions were liquidated in four hours.

“Bitcoin climbed from $76,400 on September 17 to $81,702 a day later”

Green Septembers usually mean strong Q4s

Bitcoin closed September higher in 2015, 2016, 2023, and 2024, and in each of those years the fourth quarter finished in the green with gains of 57% in 2023 and 48% in 2024. October is called Uptober because it's Bitcoin's strongest month.

“Bitcoin rose 5.2% in September 2025, then fell 23.1% in the fourth quarter, its second-worst on record behind 2018.”

But 2025 broke the pattern

Bitcoin rose 5.2% in September 2025, then fell 23.1% in the fourth quarter, its second-worst on record. The slide started in October 2025 after a tariff threat triggered $19 billion in liquidations.

“Bitcoin rose 5.2% in September 2025, then fell 23.1% in the fourth quarter, its second-worst on record behind 2018.”

Two October factors will decide 2026

Bitcoin needs a 7.7% gain from $81,214 to close 2026 above its $87,497 starting price. The fourth quarter outcome depends on whether ETF inflows return in October and whether the Fed hikes rates on October 28.

“Bitcoin needs a 7.7% gain from $81,214 to close 2026 above its $87,497 starting price”

ETF flows and Fed action are key

If ETF inflows return and the Fed pauses, Bitcoin could gain 7.7% before December. If flows stay negative and the Fed hikes again, Bitcoin might end 2026 below where it started, like it did in 2025.

“If ETF inflows return and the Fed pauses, that gain could arrive before December. If the flows stay negative and the Fed hikes again, a green September might mean what it meant in 2025”