Per-Investigator Billing Calculator

Compute per-PI vivarium charges from cage census, service usage, and per-diem rates with tier discounts, cost-share, and startup credits.

Core FacilityBillingClient-Side

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Load example per-investigator billing calculator data to see the full workflow

Billing Settings

Service Rates

Investigators

Required fields
  • Investigator 1: name is required.
  • Service rate 1: name is required.
  • Billing period start date must be YYYY-MM-DD format.
  • Billing period end date must be YYYY-MM-DD format.
  • Monthly or quarterly vivarium billing reconciliation
  • Forecasting per-PI costs for grant budgets
  • Evaluating tier discount impact on facility revenue
  • Generating per-PI invoices with service breakdowns

Don't use for

  • Setting per-diem rates (use Recharge Rate Calculator)
  • Facility-wide space allocation (use Vivarium Space Planner)
  • Grant-level budget planning (use NIH Animal Cost Budget Calculator)

Vivarium Billing Models for Core Facilities

Core facility vivarium billing involves several components:

Per-diem charges: The base daily rate per cage covers animal housing, husbandry, food, bedding, and environmental monitoring. Rates vary by species and cage type (standard, IVC, metabolic, large animal).
Service charges: Specialized services like genotyping, colony breeding management, surgical procedures, and health monitoring are billed separately at per-unit rates.
Tier discounts: High-volume investigators often receive graduated discounts to incentivize facility utilization and ensure fixed costs are distributed across a larger census.
Subsidies and credits: Faculty startup packages, department cost-share agreements, and institutional subsidies reduce the PI's out-of-pocket costs. These must be tracked and reconciled against funding sources.
Billing reconciliation: Monthly or quarterly billing cycles require cage census snapshots, service logs, and discount calculations for each PI. Discrepancies between projected and actual census are common pain points.

Frequently Asked Questions