Does it cost to send a photo through iMessage on iPhones?

I have Unlimited texts and 2GB of internet.
i do not have Wi-Fi (i know its free on Wi-Fi)
so will it cost me EXTRA if i send a photo on iMessage or will it just knock a few more extra text's off my unlimited texts?

IMessages uses data not text messages. Make sure you turn off in settings the option that says send as a text if iMessage is unavailable.

IMessage is free but remember it uses your data. So more quality pictures/videos you end will house your data. Just use unlimited text because you have unlimited text messaging