What's the cheapest way to send USDC to another address?

On each exchange, you choose the network on which you want to send a given token. USDC defaults to the ERC-20 network where costs are the most expensive. I recommend making transfers over the polygon network. REMEMBER THAT IF YOU MAKE A TRANSFER ON A GIVEN NETWORK, THE RECIPIENT'S ADDRESS MUST BE ON THE SAME NETWORK, OTHERWISE YOU WILL LOSE FUNDS. It is best to make a transfer for a small amount - the minimum payout (on Kucoin over the polygon network it is $ 5 in USDC) and then make a transfer for the target amount. Below are screenshots where these options are on KuCoin. https://www7.zippyshare.com/v/cJ7VwJVT/file.html https://www88.zippyshare.com/v/y8opfflA/file.html

You are probably talking about the commission that the exchange charges on withdrawal, not the commission of the network itself. The commission of the Ethereum network at the time of writing this is several dozen cents, although this may change in the future when the network intensity increases. In fact, the commissions of the exchanges you quote are ridiculously expensive. If I were you, I would check if the withdrawal, e.g. in BUSD, is not many times cheaper, or maybe it's better to just buy and withdraw ETH or BTC.

You can use the Ethereum network to send USDC to another address to avoid high fees. Another way is to use the Binance Smart Chain (BSC) network, where fees are usually lower. Make sure you are sending the tokens to an address that supports USDC on the network you choose.