Transfer BTCs without fees I currently have BTC 0.38 in a wallet on a computer and I want to transfer all those Bitcoins on another machine.

As I have the Bitcoins on a relatively new address (it has received 1 payment and also some Bitcoins through the move API call), it wouldn't let me transfer the Bitcoins without paying a fee.

I don't want to pay this fee, as it is pretty high for what I'm trying to transfer.

Do I just have to wait some time before spending them again to be able to do so without this fee? Or should I do something else?
The fact that you need to pay a transaction or not is determined by the priority of a transaction.

Currently the priority of a transaction is calculated with this formula.

priority = sum(input_value_in_base_units * input_age)/size_in_bytes


The minimum transaction priority for free transactions is actually 57,600,000.

Because you have all the coins in the same transaction output and I guess you will send them to one unique address the transaction size will be about 250 bytes. You have:

min_free_input_age = (min_priority_for_free_tx * size_in_bytes)/input_value_in_base_units
min_free_input_age = (57600000 * 250) / 38000000
min_free_input_age = ~378


So you have to wait 378 blocks (~3 days) before you can spend your coins without TX fee.
But note that once sent it will probably take 2 or 3 days more before the transaction will be added in a block.

Please correct me if there is a calculation error.