The December Prep Guide: 5 Tips to Prepare for Tax Season

Lya Kimbrough, MBA | Lookout Bookkeeping

Help your bookkeeper help you.

December is one of the busiest months for your bookkeeper—and one of the most important months for your business.

The smoother your year-end prep is, the easier it is for your bookkeeper to deliver clean, tax-ready books that set you up for success in the new year.

If you want to kick off January organized (and avoid back-and-forth emails), here’s the ultimate checklist to support your bookkeeper and make year-end a lot smoother.

Pro Tip #1: Make Sure All Bank & Credit Card Accounts Are Connected and Up to Date

Your bookkeeper can’t categorize what they can’t see.

Before the year ends:

• Confirm all business accounts are connected to QuickBooks
• Update passwords if needed
• Upload missing statements for any months where bank feeds didn’t pull in

The more complete the transactions, the cleaner the books.

Pro Tip #2: Answer Any Open Questions From Your Bookkeeper

If your bookkeeper has asked, “What was this transaction for?”—now is the time to answer.
Those little Amazon, Walmart, and cash transactions matter.

Clearing them up prevents:

• Wrong categorizations
• Disallowed deductions
• Delays in finalizing your books

Responding now saves everyone stress later.

Pro Tip #3: Review Open Invoices and Unpaid Bills

Your bookkeeper needs to know:

• Which invoices are still unpaid
• Which payments were received offline
• Which bills are still outstanding
• Which invoices should be written off

This helps them close income and expenses accurately.

Pro Tip #4: Gather W-9s From All Contractors You Paid $600+

Your bookkeeper must prepare 1099s in January.
Before year-end:

• List all contractors
• Confirm how much each was paid
• Collect missing W-9s
• Send everything to your bookkeeper

No W-9 = no accurate 1099.

Pro Tip #5: Tell Your Bookkeeper About Any Business Information or Structure Changes

Business owners often forget to share important updates that impact bookkeeping and taxes.
This includes:

• Address changes
• Business name/DBA changes
• Entity changes (LLC, S-Corp, partnership)
• New EIN
• Added or removed owners
• New financial accounts
• New payroll or payment platforms
• New sales tax requirements
  

Bonus Tip:
Tell your bookkeeper about these changes as soon as they happen, not months later. It keeps your books compliant and prevents major corrections down the road.

The Bottom Line

Clean books don’t happen by accident, they happen through partnership.

When you stay organized and communicate clearly, your bookkeeper can deliver accurate, stress-free, tax-ready books.

December is your chance to set yourself (and your bookkeeper!) up for success.

If you want a smooth year-end and clean books you can actually trust, LKT Bookkeeping is ready to help.