What is this page about: How custom FX rates work for your company in Light, how they interact with entity-level rates, how to request one from support, how monthly behavior works, what happens when only one currency in a pair has a custom rate, and how to check which rate was applied to a transaction.
On this page
- What a custom rate does in Light
- How to set a custom rate in Light
- How custom rates behave in Light
- Checking which rate was applied in Light
- Related articles
In Light, a custom rate lets you pin the currency conversion used for a given currency and month, instead of the daily market rate — so your books, payments, and month-end revaluation match a rate you've agreed elsewhere (for example, with your bank), rather than the market.
By default, Light converts foreign-currency amounts using daily market rates, sourced automatically. If your business reports on fixed monthly FX rates, you can have Light use your rate instead.
(Link to be confirmed before publishing — the current "Open in Light" link doesn't lead to this feature.)
What a custom rate does in Light
A custom rate pins the conversion rate for one currency, for one month. It can be set for your whole company or scoped to a single entity — if both exist for the same currency and month, the entity-level rate takes priority. Once set, every flow that converts that currency — bills, sales invoices, payments, bank reconciliation, expenses, credit notes, purchase-order matching, and the month-end FX revaluation — uses your rate instead of the market rate.
How to set a custom rate in Light
Setting a custom rate isn't self-serve yet — there's no screen for it in the product, so contact Light support with:
- Currency — the currency you want to pin (e.g. USD, GBP, CZK). It must not be EUR (see below).
- Rate — expressed as how much one unit of the currency is worth in EUR. For example, "1 CZK = 0.04 EUR." This is the same direction Light shows rates elsewhere.
- Month — the month the rate applies to.
- Scope — whether the rate should apply across your whole company, or just one entity.
Support will confirm the rate back to you before it takes effect.
Self-serve setup from your organization settings is planned for a future release. Day-level rate overrides (rather than a full month) are also planned for a future release.
How custom rates behave in Light
- Monthly. One rate per currency per month. A rate can't change part-way through a month — set a new rate for the next month instead.
- Month-scoped. A rate applies to transactions dated in its month only — it doesn't carry forward to later months, so set a rate for each month you want covered. Already-posted journal entries are never recalculated, so closed periods don't move.
- EUR is the reference currency. You give each currency's value in EUR, and Light derives the cross-rates between your currencies from that. EUR itself can't be overridden — it's the anchor.
- Set every currency you use. For a conversion between two non-EUR currencies (e.g. USD ↔ GBP), both currencies need a custom rate that month. If only one does, Light uses market rates for that whole conversion — see When Custom Rates Apply vs System Rates.
Checking which rate was applied in Light
Light keeps track of which rate was applied to each transaction, including cases where a conversion fell back to the market rate. There's no self-serve screen for viewing this yet — if you want to confirm a specific conversion used your custom rate rather than the market rate, ask Light support and they can check for you.
Related articles
Was this article helpful?
Thanks for the feedback!