Ethereum's Week. A Drop Under $2,400, a Glamsterdam Milestone, and a Missed Shot at $2,672

Ether fell to $2,398 on Tuesday, the worst level of the week, as the same failure of the CLARITY Act as Bitcoin. By Saturday, it was testing the $2,615 level, about $57 from an important level of resistance, and was backing off. Here's the latest on ether.

Tuesday, September 15: ether follows bitcoin lower

Ether followed bitcoin lower on the failure of the CLARITY Act. Ether lost 4.65% for the day to close at $2,398. Ether ETFs also lost $142 million to outflows for the day.

Wednesday, September 16: FED raises rates, Ether tests Glamsterdam

Ether rose 0.83% to $2,418 after the FED raised rates. The increase was the first since 2023. A subsequent update to the Ethereum network, Glamsterdam, was tested in a private network. During the test, 84,000 validators were run across different client software, and the limit on the block gas was increased from 60 million to 200 million. This test was successful and final. Many developers believe this will be the biggest change to the Ethereum network since the merge. Ether ETF outflows fell by $224 million.

Thursday, September 17: further Ether outflows

Ether rose 1.20% to $2,447, despite further outflows from Ether funds for a third straight day. Over the three days, a total of $405.4 million worth of Ether was sold. BlackRock's ETHA fund accounted for the lion's share of the selling.

Sept. 18: Rally arrives, flows turn positive

Ether jumped 6.74% to $2,612 this week as positive sentiment in the market lifted the price of Bitcoin and other cryptos. ETF inflows of $29.4 million were led by Fidelity's FETH with $26.2 million. After three consecutive down days, this was a welcome move for Ether ETFs.

ETH/USD, Sept. 15-20, 2026

The remainder of the week, Sept. 19-20:

Ether settled at $2,615 on Saturday for a gain of 0.10% and the week's high. It was trading at about $57 from the $2,672 Fibonacci level that many traders see as critical to a move above $3,000. Ether was trading at about $42 from that level earlier in the day. Ether pulled back from that level on Sunday and was trading in the $2,580 to $2,600 range.

US Spot Ethereum ETF Net Daily Flows, 15 - 18 September, 2026

What the recent test run means

The success of Devnet 11 on September 16 would theoretically allow client teams to begin testing on Sepolia, Ethereum's public test network, on October 6. Developers have expressed concern about Sepolia testing, particularly as client teams have to submit updated code by September 29. Researchers have raised concerns about “builder” accounts, where a single entity creates multiple account IDs to manipulate and disrupt the new and forthcoming client and block auction systems. Sepolia testing should identify and resolve issues that may help inform block producer and client implementations. It is currently the plan of the Ethereum community to test Hoodi following the completion of Sepolia testing, with mainnet activation still targeted broadly for the fourth quarter of this year.

What it Means

$2,360 was the low on Tuesday that held all week. It marked the floor, and we'll consider $2,672 the ceiling for the near term. The level originates from the Fibonacci retracement of Ether’s (ETH) decline from the 2025 peak to the 2026 ETH Jan low. A move above $2,672 would open a possible move toward the $3,000 level in the near term. Other analyses indicate that ETH needs to hold $2,600 to $2,616 as support for that potential move to $2,672 and ultimately $3,000 to stay open. Analysts also indicated $2,750 and $2,800 as the next resistance levels above that.

The long-term ETH ‘ETF’ story is also interesting. ETH funds took approximately 3 days to turn positive this week, and the ETH rebound was less than a third of the size of the Bitcoin rebound. It is worth noting that the ETH and Bitcoin funds may be correlated, but do not move in perfect sync.