Last updated: March 20, 2026
If you are a contractor struggling to see which projects are actually making money, mastering job costing in QuickBooks Online is the single most important move you can make. This guide is for construction business owners who want to move past "bank balance accounting" and see real-time profitability per project through automated workflows and precise cost tracking.
We will cover exactly how to set up your Chart of Accounts, how to track labor and materials by project, and the specific reports you need to stay in the black.
Why is construction bookkeeping different from regular accounting?
Standard businesses usually care about their total income and total expenses for the month. However, for a contractor, a single high-revenue month can hide a disastrous project that is bleeding cash. Construction bookkeeping requires a granular approach because you are essentially running several "mini-businesses" (your projects) simultaneously.
Specifically, you need to track "job costing," which is the process of assigning every single dollar spent to a specific project. If you buy a box of nails, your books should show whether those nails went to the Smith Remodel or the Johnson Deck. Without this level of detail, you might think you are profitable because your bank account has a high balance, but you could actually be losing money on your current active jobs.
Furthermore, the construction industry deals with unique financial elements like retainage, progress billing, and specialized labor burdens. Managing these requires more than just basic bookkeeping services; it requires a system that understands the lifecycle of a build.
How do you set up QuickBooks Online for construction projects?
Setting up QuickBooks correctly from day one prevents a massive cleanup headache six months down the road. Initially, you should ensure you are using QuickBooks Online Plus or Advanced, as these versions offer the "Projects" feature which is non-negotiable for job costing.
First, you need to configure a construction-friendly Chart of Accounts. Instead of just "Materials," you might want sub-accounts for lumber, electrical, and plumbing. This allows you to see exactly where your estimates might be falling short.
Next, you should enable the Projects feature in your settings. This creates a dedicated hub for every job where you can see income, expenses, and profit margins at a glance. You will also want to set up your "Products and Services" list to match your common cost codes. When you categorize an expense to a specific service linked to a project, QuickBooks automatically does the math for you.
Lastly, don't forget to import your vendor and subcontractor information properly. Ensuring that every subcontractor is marked for 1099 tracking is a small step that saves hours of stress during January’s tax season.
What is job costing and why does it matter for your margins?
Job costing is the heartbeat of a successful construction company. By tracking every expense, from the large lumber delivery to the small permit fee, against a specific project, you gain total visibility into your margins. Consequently, you can identify "scope creep" before it ruins your profit.
When you master job costing, you can compare your "Estimated vs. Actual" costs in real-time. If you estimated $5,000 for labor on a kitchen remodel but the report shows you’ve already spent $4,800 and the cabinets aren't even in yet, you know you have a problem. This data allows you to have tough conversations with clients or adjust your future bidding process immediately.
Moreover, accurate job costing helps with Work-in-Progress (WIP) reporting. This is essential for larger contractors who need to show bonding companies or banks how much of their current work is under-billed or over-billed. It transforms your books from a historical record into a management tool.
How do you track labor and materials effectively?
Labor is often the most difficult expense to track because it isn't always documented with a neat invoice from a vendor. To get this right, you should integrate a time-tracking tool like QuickBooks Time (formerly TSheets) directly with your accounting software. Employees can clock into specific jobs on their phones, and those hours flow directly into your project costs.
Materials require a different kind of discipline. Every time you or a foreman uses a company credit card at Home Depot, that receipt needs to be coded to a specific job. Many small business bookkeeping workflows fail here because receipts get lost in the truck. Using an app like Dext or the QuickBooks mobile app to snap photos of receipts ensures they are categorized and attached to the project instantly.
Additionally, you should implement a "Purchase Order" system for large material buys. By creating a PO in QuickBooks and then matching it to the vendor's bill later, you ensure that you are only paying for what was authorized and that the cost is assigned to the correct project estimate.
What are the most common construction bookkeeping mistakes?
One of the most frequent errors we see at Books LA is the "commingling" of project funds. Contractors often use the deposit from Job B to pay the subcontractors for Job A. While this keeps the lights on temporarily, it creates a "rob-Peter-to-pay-Paul" cycle that makes it impossible to know if either job is actually profitable.
Another common mistake is failing to record change orders immediately. If a client asks for a different tile mid-project, that expense and the additional revenue must be added to the project in QuickBooks. Otherwise, your job costing reports will show you went over budget, when in reality, you just didn't update the plan.
Finally, many contractors forget to account for "indirect costs" or overhead. While it’s easy to track the wood used on a house, it’s harder to track the fuel for the trucks or the insurance premiums. Successful contractors often use a "burden rate" to apply a portion of these costs to each job to get a true picture of their net profit.
When should you hire professional bookkeeping services for your construction business?
If you are spending your Sunday nights hunched over a laptop trying to figure out why your project reports don't match your bank balance, it’s time for help. Professional construction bookkeeping is an investment that usually pays for itself by catching missed billings and identifying unprofitable workflows.
As your business scales from a crew of two to multiple teams on different sites, the complexity of payroll, lien waivers, and progress billing becomes a full-time job. A specialized bookkeeper ensures that your data is clean, your subcontractors are paid on time, and your CPA has everything they need for year-end without a "cleanup" fee.
At Books LA, we specialize in helping Los Angeles contractors get their systems out of their heads and into a scalable, automated workflow. We handle the day-to-day data entry so you can focus on the job site and growing your revenue.
About the Author
Jelena Arkula is the owner of Books LA, a boutique accounting firm based in Los Angeles. With years of experience helping local businesses master QuickBooks Online and Xero, Jelena and her team specialize in turning "messy books" into clear, actionable financial roadmaps.
Disclaimer: Books LA provides bookkeeping and specialized construction accounting support. We do not provide income tax advice; we work alongside your CPA to ensure they have perfect data for your tax filings. Always confirm specific tax strategies with a qualified tax professional.
Frequently Asked Questions
1. Can I use the basic version of QuickBooks for construction?
Not effectively. You really need QuickBooks Online Plus or Advanced to access the "Projects" and "Job Costing" features that make construction accounting possible.
2. What is "Retainage" and how do I track it?
Retainage is a portion of the contract price (usually 5-10%) withheld by the client until the job is finished. In QuickBooks, you should set up a specific "Retainage Receivable" account to track this money so you don't forget to bill for it at the end.
3. Is job costing worth the extra time?
Absolutely. Without it, you are guessing at your profits. Job costing tells you exactly which types of projects are making you money and which ones you should stop bidding on.
4. How often should I reconcile my construction books?
You should aim for at least once a month, but high-volume contractors benefit from weekly reconciliations. This ensures your project reports are always current when you are making buying decisions.
5. Do I need a separate bank account for every project?
No, that would be a logistical nightmare. Instead, use one business account and use QuickBooks "Projects" to virtually separate the money.
6. What is the difference between a bookkeeper and a CPA for contractors?
Your bookkeeper (like Books LA) handles the daily transactions, project tracking, and payroll. Your CPA uses that clean data to file your annual income tax returns and provide high-level tax strategy.
7. How do I handle 1099s for subcontractors?
QuickBooks makes this easy if you collect W-9s upfront. You simply mark the vendor as "Eligible for 1099" and the software tracks their payments throughout the year for January filing.
