[jaycroft]

At this moment, on Coinbase, you can instantly sell approximately 1000 BTC for $9.91M - about 4% under the mid market price against what is on the book. Assuming you are a US person (since you want to move the money to a US bank) and have no problem complying with their KYC policies, you should be able to get the money a day or two if you chose to accept a wire instead of an ACH. Just for comparison, for ACH in particular since you mention it, most traditional trading institutions (etrade, schwab, ameritrade) limit your ACH transfers to 250k/day - coinbase does as well last I checked. So you'd get your money about 10x as fast as if you tried to do it via ACH. Wires are typically unlimited.

Snapshot of live book depth at time of posting: https://imgur.com/a/rhi7ZKL

Taken from here, look for "view exchange": https://pro.coinbase.com/trade/BTC-USD

[jjeaff]

Coinbase has a $10k per day withdrawal limit. You have to contact them to get more. They don't specify how difficult or time consuming that process is.

[gunshai]

It seriously isn't that difficult to get this limit increased.

Speaking as someone who watched a buddy go through this process it took him ~2 days to get his limit increased to the millions for a wire transfer.

[spookthesunset]

In other words, it is not possible.