Definition
Submetering is a utility billing approach where a property installs submeters for individual units (or tenant spaces) to measure actual consumption of utilities such as water, electric, or gas. Residents are then billed based on their usage, rather than the owner paying a master bill or allocating costs using estimates.
How It Works
Many properties receive utilities through a master meter (one bill for the entire building). Submetering adds a second layer of metering at the unit level. A billing company or property manager collects readings (manual or remote), calculates charges, and bills residents—often alongside rent.
Common setups
- True submetering: unit-level meters measure actual usage (kWh, gallons, therms).
- RUBS (allocation): costs are allocated by a formula (e.g., occupants, square footage) without measuring actual usage.
- Hybrid: submeter water, allocate sewer/trash, or submeter electric while owner pays common-area loads.
Why It Matters
Submetering can improve NOI by shifting utility costs from owner to resident (where allowed), increasing utility reimbursements, and encouraging conservation. It also reduces “free utility†behavior because residents see a direct connection between consumption and cost.
Investor Uses
- Underwriting value-add: model utility reimbursements and reduced owner-paid expenses.
- Stabilizing NOI: reduce volatility from rising utility rates by passing through usage.
- Behavioral leverage: conservation typically increases when usage is measured and billed.
- Leak detection: abnormal readings can flag leaks or failing fixtures faster.
What Gets Billed
- Water: usage (gallons) plus service fees; sewer may be tied to water usage or billed separately.
- Electric: unit consumption (kWh) with time-of-use or tiering depending on provider and system.
- Gas: heating/cooking usage (therms) where unit-level distribution supports metering.
- Common-area utilities: typically remain owner-paid and are not billed to residents unless allocated by policy.
Example
A 100-unit property is master-metered for water and the owner pays $18,000/month for water/sewer. After installing water submeters and implementing a compliant billing program, the property bills residents $12,000/month in water reimbursements and reduces overall consumption so the master bill falls to $15,500/month.
- Owner utility expense change: $18,000 → $15,500 (savings of $2,500/month)
- New reimbursement income: $12,000/month
- Total NOI lift (before admin costs): $2,500 + $12,000 = $14,500/month
In practice you would subtract billing/admin fees and account for any caps, affordability rules, or vacancy effects.
Common Pitfalls
- Regulatory compliance: local and state rules may limit how and what you can bill back.
- Resident friction: sudden bill-backs can increase churn if not communicated and phased thoughtfully.
- Metering limitations: some building designs (older plumbing stacks) make true submetering expensive or impractical.
- Bad data: misreads, broken meters, or poor calibration can create disputes and revenue leakage.
- Not modeling offsets: billing programs often have admin costs, caps, and vacancy sensitivity—underwrite net, not gross.