---
title: "Rate Guard and the margin floor"
description: "The two Pro controls that exist for one specific fear: the rate moved overnight and you sold a week of stock below cost."
url: "https://maksut.net/price-anchor/docs/rate-guard-and-margin-floor/"
language: "en-US"
datePublished: "2026-08-02T00:35:16+00:00"
dateModified: "2026-10-10T08:40:00+00:00"
---

# Rate Guard and the margin floor

For a merchant importing in USD and selling in a volatile local currency, the fear is not “I cannot add GBP”. It is *“the rate moved 12% overnight and I sold a week’s stock below cost.”* These two features exist for that sentence.

## Rate Guard

Rate Guard watches the size of a rate movement and, past your configured threshold, holds the new table instead of applying it. Nothing reaches the catalogue until a human approves it.

- Both **one-step** and **cumulative** movement are considered, so a rate that drifts 3% a day for four days does not slip under a 10% single-step threshold.
- A held table waits on the **Approval** tab with the old and new rates side by side.
- Approving applies **the exact table you reviewed**, stored through the free plugin’s own rate repository, followed by the normal rates-updated event. It does not refetch. A merchant who approves a 12% move must not silently receive a 25% one — that is the precise failure the guard exists to prevent.
- Because approval re-applies a table already on disk, it keeps working while the provider is down.
- Discarding a held table leaves your last known good rates in place.

If Pro is deactivated while a table is held, the held row stays on disk but nothing reads it. The free plugin applies the next update normally, and reactivating Pro finds the hold still waiting.

## Minimum margin floor

The floor prevents a calculated selling price from falling below the locked acquisition cost plus your configured minimum margin. It is applied after rate and markup and remains effective after rounding, so a rounding rule cannot round a price back under the floor.

The floor depends on [locked acquisition cost](https://maksut.net/price-anchor/docs/acquisition-cost-and-profit/). A product with no recorded cost has no floor to enforce — the plugin does not invent one from the current market rate.

## Price freezes

A freeze pins chosen products or categories against rate movement entirely. Frozen products are skipped by repricing passes and keep their current price until you unfreeze them.

Use it for a printed catalogue, a contracted price, a campaign with a promised price, or anything where the commercial commitment outranks the exchange rate. If Pro is deactivated while a freeze is active, frozen products rejoin normal syncing on the next pass.

## Choosing thresholds

There is no universal number. A practical approach: look at your currency pair’s actual daily movement over the last year, take a value that would have triggered a handful of times rather than weekly, and start there. A guard that fires every day trains you to click Approve without reading, which is worse than no guard at all.