CAM Reconciliation Accounting Best Practices for Property Managers

For commercial property managers, Common Area Maintenance (CAM) reconciliation represents one of the most consequential financial processes of the year. Industry analyses from organizations such as BOMA International and the Institute of Real Estate Management (IREM) frequently find that CAM reconciliations and expense classifications are among the most frequent drivers of landlord-tenant disputes, with unclear statements and misclassified expenses cited as leading contributors.

The impact of an incorrect CAM reconciliation isn’t just limited to tenant disputes, however. Inaccurate reconciliations either leave legitimate revenue uncollected or expose landlords to costly disputes and audit challenges. Because CAM recoveries flow directly into Net Operating Income, errors don't just create disputes: they distort the property's financial performance.

Understanding CAM Reconciliation as Year-Round Discipline

CAM reconciliation is the year-end process of comparing estimated CAM charges billed throughout the year against actual common area expenses incurred. The objective is to ensure each tenant pays their proportionate share of legitimate costs.

Most commercial leases require these reconciliations to be completed within 30 to 90 days following fiscal year-end. During this window, you'll identify whether monthly estimates resulted in tenant overpayments (requiring credits or refunds) or underpayments (requiring additional invoicing).

The difference between smooth reconciliations and contentious ones typically isn't the complexity of year-end calculations: it's the quality of systems maintained throughout the preceding twelve months.

Critical Components of Every Reconciliation

There are several fundamentals that are important to a pain-free CAM reconciliation. They include: 

• General ledger verification requires confirming every expense is properly coded within the real estate chart of accounts to the correct account and property, with supporting invoices retained. Errors and misclassifications compound monthly; by December, they are extremely difficult to unwind cleanly without outsourced accounting support.
  
  
• Pro-rata share calculations determine each tenant's proportionate responsibility based on occupied square footage relative to total leasable area. In large portfolios, even small, property-level errors can have a significant impact on performance. 
  
  
• Gross-up adjustments allow landlords to adjust variable expenses to a 95% or 100% occupancy baseline when properties have vacancies, preventing current tenants from subsidizing vacant space. These provisions must be explicitly stated in lease agreements and applied consistently.
  
  
• Lease-specific exclusions require meticulous attention. Individual agreements often stipulate expenses tenants aren't obligated to pay, such as capital improvements, certain administrative fees, or property-specific costs. 
  
  
• Tenant transition adjustments ensure fairness for those who moved in, moved out, expanded, or contracted during the year. Consider a retail tenant who expanded from 3,000 to 6,000 square feet in July—you'll need two reconciliations covering each period. 

ASC 842 Implications

Under current lease accounting standards (ASC 842), CAM charges are generally treated as non-lease components, accounted for separately from base rent. For property managers, ASC 842 reinforces the need to track CAM expenses in dedicated general ledger accounts segregated by category: utilities, janitorial services, landscaping, security, parking lot maintenance, snow removal, property management fees, and so on. 

Beyond compliance, this structure pays practical dividends at reconciliation time. When recoverable expenses live in distinct accounts, you can run a P&L or trial balance and pull the relevant totals directly rather than combing through mixed accounts to separate what's recoverable from what isn't.

This categorization simplifies tenant-facing reconciliation statements while ensuring your income reporting properly distinguishes between base rent revenue and CAM recoveries. Accurate segregation also ensures CAM recoveries are not inadvertently overstated as rental income; an issue auditors will flag in your real estate financial statements.

Related: Property Management Accounting: The Complete Guide

Building the Foundation: Year-Round Systems

Successful reconciliation begins in January, not December. Small coding errors snowball throughout the year. Waiting until December to correct them guarantees friction.

Every CAM expense should be recorded promptly with proper account coding, supporting documentation retained, and vendor invoices filed systematically. Property management software platforms offer CAM-specific modules that reduce the categorization errors triggering tenant disputes.

Create lease abstracts for each tenant outlining specific CAM obligations: exact pro-rata share percentage, negotiated exclusions, expense caps, gross-up provisions, and audit rights. Include each lease's renewal date in your tracking system—renewals often reset base year expenses or adjust pro-rata percentages, and missing these changes will carry forward incorrect calculations until someone catches the error. Track tenant changes, including move-ins, move-outs, expansions, and contractions, throughout the year.

The Reconciliation Process

Start with rigorous general ledger review. Verify every expense is coded to the appropriate CAM account, assigned to the correct property, and supported by proper documentation. Specific areas that you might want to look for include capital improvements incorrectly coded as operating expenses, tenant-specific costs included in the CAM pool, or personal expenses charged to property accounts.

The distinction between repairs (operating expenses recoverable through CAM) and improvements (capital expenditures that must be amortized) has significant financial implications. Patching a parking lot qualifies as maintenance; repaving the entire lot typically constitutes capital improvement. Misclassifying these costs can result in improper tenant billings, disputed reconciliations, and exposure to lease challenges or audit adjustments.

Calculate allocations with precision. Divide each tenant's occupied square footage by total leasable square footage, then apply that percentage to total CAM expenses. Apply tenant-specific adjustments: account for mid-year space changes, apply expense caps, and honor negotiated exclusions.

Prepare transparent reconciliation statements including itemized CAM expenses by category, pro-rata share calculations, total estimated charges paid, total actual charges owed, and net true-up amount. Attach supporting documentation. Maintaining clear statements that show your work simplify the process of audit preparation. 

Building Trust Through Professional Execution

The quality of your reconciliation process directly shapes tenant relationships. Clear, accurate statements delivered on time signal operational competence; while inaccurate calculations and missing documentation erode trust and invite scrutiny. Many commercial leases grant tenants audit rights, and property managers who can produce clean supporting materials within days of a request build credibility that discourages future challenges.

Proactive communication matters as much as accuracy. If CAM costs increased substantially due to major repairs, insurance premium spikes, or new service contracts, a brief explanation sent before the reconciliation statement provides context and gives tenants time to budget rather than react defensively to an unexpected invoice.

Given the stakes—tenant retention, audit exposure, and direct impact on NOI—many property management firms and commercial real estate investors outsource CAM reconciliation to specialized accounting partners. This ensures consistent execution, frees internal teams for higher-value work, and provides confidence that reconciliations will withstand tenant scrutiny.

When Specialized Financial Support Adds Value

CAM reconciliation demands both technical accounting expertise and deep understanding of commercial lease structures. If your organization experiences any of the following challenges, it’s a sign that you might be better served by specialized commercial real estate accountants:

• Growing portfolio complexity making reconciliations increasingly time-consuming
• Limited in-house accounting resources with CAM-specific expertise
• Recurring tenant disputes over reconciliation accuracy
• Concerns about ASC 842 compliance

G-Squared Partners works with commercial real estate clients to ensure their accounting operations produce accurate, audit-ready financial reporting. Our team brings specific expertise in commercial lease interpretation, ASC 842 compliance, and reconciliation processes that minimize disputes while maximizing appropriate cost recovery.

Ready to strengthen your property management accounting operations? Contact G-Squared Partners to learn how our fractional CFO and outsourced accounting services can streamline your CAM reconciliation process and give you confidence in your financial reporting.