> ## Documentation Index
> Fetch the complete documentation index at: https://docs.hyperline.co/llms.txt
> Use this file to discover all available pages before exploring further.

# Retroactive subscription update

> Apply a Hyperline subscription change retroactively after the current period is already invoiced, using the advanced update flow with transition invoice.

Sometimes you need to update a subscription after the current billing period has already been invoiced — for example, you forgot to apply a price increase at renewal, a contract amendment was signed late, or an extra product should have been added at the start of the period.

This guide walks you through how to apply a subscription change retroactively using the [advanced update](/docs/subscriptions/update#advanced-update) flow, with either **At last renewal** or **At selected date**, and explains how each transition invoice mode (**Generate transition invoice** vs **Refund and re-invoice**) impacts the customer's invoices.

## When to use a retroactive update

Use a retroactive update when:

* The change should have taken effect earlier in the current billing period (or in a past period)
* The invoice for the current period has already been issued and you want to correct it
* You need a clean audit trail and version history of the change

If the change can simply apply going forward, use **Next renewal** or **Immediately** instead — there's no need for a retroactive update.

## Choose when to apply the update

In the advanced update flow, the **When to apply the update** step controls the effective date of the change:

* **At last renewal** — Applies the update retroactively as of the start of the current billing period. This is the most common option when you want the change to look as if it had been configured from the beginning of the period.
* **At selected date** — Applies the update at a specific date you pick. Choose a **date in the past** to make the change retroactive to that exact day (for example, mid-period when a contract amendment was signed).

<Card title="Example 💡">
  A subscription renewed on **March 1st** with a monthly plan at €100. On **March 20th** you realize a new add-on should have been included since March 1st.

  * Select **At last renewal** to apply the add-on as of March 1st — the full period is recalculated as if the add-on had always been there.
  * Select **At selected date** and pick **March 10th** if the add-on should only apply from that day onward — the period is split, and only the portion after March 10th includes the add-on.
</Card>

## Choose the transition invoice mode

Once you've picked the retroactive effective date and the new subscription configuration, the **Configure transition options** step lets you decide how the already-issued invoice should be corrected. Two modes are available for retroactive updates:

### Generate transition invoice

A single **transition invoice** is issued on top of the existing invoice to settle the difference between what was originally billed and what should have been billed for the period.

* The original invoice for the current period is **kept as-is** (not refunded)
* A new invoice is generated for the **delta** — either a charge (if the customer owes more) or a credit note (if the customer was overcharged)
* Best when you want a lightweight correction and to preserve the original invoice for accounting continuity

<Card title="Example 💡">
  Original invoice for March: **€100** (already paid).

  You apply a retroactive update **At last renewal** to add a €30/month add-on.

  With **Generate transition invoice**, Hyperline issues an additional invoice of **€30** for March. The customer keeps their original €100 invoice and receives a second €30 invoice covering the add-on for the same period.
</Card>

### Refund and re-invoice

The original invoice for the current period is **fully refunded** (via a credit note), and a brand new invoice is issued reflecting the updated subscription configuration.

* The customer ends up with one credit note cancelling the original invoice, plus a new invoice for the corrected amount
* Best when the original invoice is materially wrong and you want the final billing to look as if the new configuration had been in place from the start of the period
* Only available for updates **At last renewal**

<Card title="Example 💡">
  Original invoice for March: **€100** (already paid).

  You apply a retroactive update **At last renewal** to swap the plan from €100/month to €150/month.

  With **Refund and re-invoice**, Hyperline issues a **credit note of €100** cancelling the original invoice, and a new **€150 invoice** for March reflecting the new plan. The customer's net balance for the period is now €150 instead of €100.
</Card>

<Note>
  **Refund and re-invoice** is only available when applying the update **At last renewal**. For updates **At selected date** in the past, use **Generate transition invoice** to settle the delta.
</Note>

## Step-by-step instructions

<Steps>
  <Step title="Open the subscription and start an update">
    Navigate to the customer's subscription details page, click the **Actions** dropdown, then select **Update subscription**.

    Choose **Advanced update** to access the full transition configuration.
  </Step>

  <Step title="Choose when to apply the update">
    Select either:

    * **At last renewal** to apply the change retroactively from the start of the current billing period
    * **At selected date** and pick a date in the past for a mid-period retroactive change
  </Step>

  <Step title="Choose the update source">
    Select **Update current subscription** to edit the existing configuration, or **Update to a template or a plan** to reset the configuration from a template or plan. Make the changes that should have been in place as of the effective date (add a product, change a price, swap the plan...).
  </Step>

  <Step title="Configure transition options">
    Under **Transition invoice**, choose how to correct the already-issued invoice:

    * **Generate transition invoice** — issues an additional invoice for the delta, keeping the original invoice intact
    * **Refund and re-invoice** — refunds the original invoice and issues a new one reflecting the updated configuration (only with **At last renewal**)

    <Tip>
      Use the invoice preview at this step to review both the transition invoice (or refund and new invoice) and the following invoice. This is the safest way to confirm the financial impact before applying the change.
    </Tip>
  </Step>

  <Step title="Review and confirm">
    Review the update summary, then confirm. The subscription is updated retroactively and the corresponding invoices (transition invoice, or credit note and new invoice) are generated immediately.
  </Step>
</Steps>

## What happens after the update

* The subscription configuration reflects the change as of the effective date
* The corrective invoices (transition invoice or credit note + new invoice) are issued and follow your usual collection rules
* The change is recorded in the [versions tab](/docs/subscriptions/update#subscription-versions), preserving a full audit trail of what changed and when

<Info>
  Is something still unclear? Don't hesitate to reach out to our team via the in-app chat if you need additional support.
</Info>