Cost history

ProTally keeps a complete history of every cost you record, so changing a cost never rewrites the past.

Why history matters

Costs change over time, but the profit on a sale that already happened shouldn't change with them. ProTally solves this by versioning costs: each cost you record has a start date, and a sale is always costed using the cost that was active on the day it was paid.

That means you can update a price's cost whenever your real costs change, confident that historical reporting stays accurate.

Viewing a price's cost history

  1. Go to Settings → ProTally → Product Costs and open a product.
  2. On the Price & Costs screen, open the ⋯ menu next to a price and choose Cost history.

The Cost History screen lists every cost recorded for that price, newest first:

  • The most recent cost carries an Active badge and shows "Active from" its start date.
  • Older costs are listed as historical, each showing "Effective from" its start date.

Each entry displays the cost itself — a per-unit amount, or a summary for tiered costs.

Adding a new cost

Rather than editing an existing cost, the cleanest way to reflect a change is to add a new one:

  1. On the Cost History screen, click Add cost entry.
  2. Enter the new cost and set the Start Date to when it takes effect.
  3. Click Save Cost.

The new cost becomes Active, and the previous one moves into history. Sales before the new start date keep using the old cost; sales on or after it use the new one.

Editing an existing entry

Select any entry in the history list to open it in the cost form, adjust the values or start date, and click Update Cost.

Editing rewrites that period

Editing an existing cost entry changes how sales in that period are costed. If your goal is to record a genuine change in cost going forward, add a new entry with a later start date instead — that preserves an accurate audit trail.

Where to go next