FOCUS column
ChargePeriodStart
The inclusive start of the interval the individual charge covers, which is finer than the billing period: an hour, a day or the usage window of one line item. It is what daily reporting and anomaly detection are built on, since the billing period only says which invoice a row belongs to.
Example
An hourly compute charge for 14:00 to 15:00 UTC on 12 September carries 2026-09-12T14:00:00Z here.
Where it comes from, per export
The export column that feeds ChargePeriodStart in each format the platform ingests, and the transform applied. A format with no row does not carry the column; the value is then absent rather than guessed.
| Export | Source column | Transform |
|---|---|---|
| AWS Data Exports, FOCUS | ChargePeriodStart | as is |
| Azure Cost Management, FOCUS export | ChargePeriodStart | as is |
| Azure Cost Details (actual cost) | Date | parsed as a date (MM/dd/yyyy) |
| Azure Cost Details (amortized cost) | Date | parsed as a date (MM/dd/yyyy) |
| Google Cloud detailed billing export | usage_start_time | cast to datetime |
How Runcost uses it
Runcost learns daily baselines and flags anomalies on charge periods, so a spike is seen the day it starts rather than at month-end.
Related columns
About this reference
Generated from the column contract and provider rules that Runcost runs, and written by Faisal Saleem, Founder. The normative definitions are in the FinOps Foundation’s FOCUS specification at focus.finops.org.