Situation:

I have $1300 in debt on one of my cards at the moment, and about $300 in my checking account.

Due to my new job working for the state, there is a lag of anywhere from 1-10+ weeks between start of job and first check. I am currently completing my second full pay cycle without a cent, so I'd like to somehow keep my balance from rising too fast.

I have convinience checks from the same credit card, offering a 3.99% rate on it. This is what I want to do:

Write a check to myself for $1300. Use the funds to pay off the $1300 I have on the card already, which is running at 10.74% interest.

Will the net result be $1300 debt at 3.99% instead of $1300 at 10.74%? Will the $1300 payment just cancel out the new debit for the check itself?

Well... if you write the check to yourself, you'll have $1300 at 10.74% and $1300 at 3.99%... (plus whatever "cash advance fee" they charge -- most likely that will also be at 10.74%)...

Then you write a check to the CC company for $1300.

What happens now depends entirely on your CC company and their Terms and Conditions... I can virtually guarantee that if you just send them the check they'll apply it to the 3.99% balance. If you specifically tell them that it's being sent to cover the 10.74% balance? They may do what you want, or they may still apply it to the 3.99% balance. Sounds like time to read the fine print - it will probably say somewhere that all payments will be applied to the lowest rate balances first.

For this to work guaranteed, you pretty much need another card with another company.

It's also worth noting that it won't work at all unless you have at least a $2700~ limit on the card...

I like steveh's idea, & think it'll work.