Is there a gas difference between minting and sending ERC-20 tokens?

Question

Is there a large difference in the cost of gas when you mint tokens in a pre-existing ERC-20 contract, versus sending that same token?

One example would be when an AMM like Uniswap wants to send tokens to an LP - one transaction would be to mint tokens as they are earned, and another would be to send pre-existing tokens as part of an airdrop.

My guess is that minting would be more expensive, because you are adding a new owner address to the token. This requires additional memory.

But assuming that you can mint coins directly to an address, it wouldn't be substantially more expensive. You wouldn't need to have to separate steps of minting and then sending.

Answer 1

The transaction will be a change in a mapping from the smart contract. Each entries cost gas as it's described on yellow paper : https://ethereum.github.io/yellowpaper/paper.pdf

Page 25.

If you "mint" a token, I think it modify an entry on mapping as : address 0x000000 mint X tokens.

If someone transfer token, you will add token to another address AND substract to another, so you will have 2 entries.

address 0x000000 lost X tokens. address 0x111111 gain X tokens.

So yeah they will be a difference.