over draft..

i have a question please, on my online account with halifax, it said that  can change my over draft limit so i did from 0 to 100, i dont need as i dont use this account and i have few hundred pounds in it for emergency , my question is will i be charged a penlaty or interest even if i dont use it? thanks....

you wont be charged for the overdraft if you dont use the overdraft.
but you might want to make sure your account is not a fee-paying account... some types of accounts have a monthly fee of £5 or £10.

thanks a bunch!:)