I was just wondering, is there a way to transfer dilithium to another character on your account?

either as refined or unrefined

or is the only way to change it to c-points, then change it back on the other account?

No. The only way to do it is the CPoint way I'm afraid.

Which isn't a bad way to do it if you don't mind a slight loss, the extange only varies by 1 point usually between buying and selling, you won't lose much, less then a third of a percent...

The way i do it is to put a order to buy C-Points in the Exchange, at a very low value like 50 dil to C-Points. Then I switch to my other toon, and cancel the order to buy and withdraw the dil. done and transferred with no loss

So the answer must be, YES you can.

Yup, WIlliam has the correct method.

You don't even need to switch toons, just cancel it and don't withdraw it, until your on the toon you want.