I am splitting a Home Office Rent expense as 70% personal and 30% business. How can I categorize this transaction so that only the business part gets deducted in the books?

Check with your Accountant to make sure you're doing it the way they want it shown.  And I'm also assuming that 30% number came from the Accountant, if not you need to ask them that as well.  I can't take anywhere near 30% off my taxes for a home office.

What they very well may tell you to do is to calculate the X% they tell you that can be expensed of the annual cost and pay that amount out of the Company Checking Account.  You cannot transfer the money into your personal account, you need to actually pay the bill for that amount from the company to the vendors.  But again, this is something you REALLY need your Accountant to tell you, not to go on what anyone here tells you.

How you show it is pretty straight forward.  The check you write to your power company would go to a Utilities Expense Acct, etc.  Again, just find out what the Accountant wants these Accts called.

Thank you for your response. Sorry I actually got it confused. I’m meaning to say 70% personal and 30% business. I have not consulted an accountant yet, just trying to estimate the actual space the business is occupying. 

So are you saying I need to deliver 2 checks to my landlord - one from the business checking to cover the business part, and the remaining amount from my personal checking account?

Thank you for your response. Sorry I actually got it confused. I’m meaning to say 70% personal and 30% business. I have not consulted an accountant yet, just trying to estimate the actual space the business is occupying. 

So are you saying I need to deliver 2 checks to my landlord - one from the business checking to cover the business part, and the remaining amount from my personal checking account?