> AI agents: this is one page from PostHog's docs. Full index of Markdown docs for LLMs: https://posthog.com/llms.txt

# Linking Flexmail as a source

Canonical URL: https://posthog.com/docs/data-pipelines/sources/flexmail

> **Cloud region:** This page uses US Cloud hosts. For an EU Cloud project, use `https://eu.posthog.com` instead of `https://us.posthog.com` or `https://app.posthog.com` (app host for links).

## On this page

- [Prerequisites](#prerequisites)
- [Adding a data source](#adding-a-data-source)
- [Sync modes](#sync-modes)
- [Configuration](#configuration)
- [Supported tables](#supported-tables)
- [Troubleshooting](#troubleshooting)

**Beta release**

This source is currently in **beta**. It works end to end, but you may still hit rough edges. [Let us know](https://us.posthog.com/#panel=support%3Asupport%3Adata_warehouse%3A%3Atrue) if you do.

![](https://res.cloudinary.com/dmukukwp6/image/upload/texture_tan_9608fcca70)

![](https://res.cloudinary.com/dmukukwp6/image/upload/texture_tan_dark_a92b0e022d)

Let AI connect your sources for you

Skip the manual setup — run this in your project and the wizard auto-detects your databases and APIs and connects them to PostHog.

`npx @posthog/wizard warehouse`

![PostHog Wizard hedgehog](https://res.cloudinary.com/dmukukwp6/image/upload/wizard_3f8bb7a240.png)

![](https://res.cloudinary.com/dmukukwp6/image/upload/wizard_3f8bb7a240.png)Let AI connect your sources for you

The Flexmail connector syncs contacts, custom fields, interests, and more into the PostHog data warehouse, so you can analyze them alongside your product data.

## Prerequisites

Credentials that can read the data you want to sync. PostHog only reads data, so read access is enough.

## Adding a data source

1.  In PostHog, go to the [Sources tab](https://app.posthog.com/data-management/sources) of the data pipeline section.
2.  Click **\+ New source** and click **Link** next to this source.
3.  Enter your credentials (see [Configuration](#configuration) below) and click **Next**.
4.  Select the tables you want to sync, choose a sync method and frequency, then click **Import**.

Once the syncs are complete, you can start querying this data in PostHog.

Enter your Flexmail account ID and personal access token to pull your email marketing data.

You can create a personal access token under **Settings → API → Personal access tokens** in [Flexmail](https://app.flexmail.eu). The token grants read access to your contacts, interests, custom fields, preferences, segments, sources, and opt-in forms.

You'll be asked for:

-   **Account ID**
-   **Personal access token**

## Sync modes

Each table can be synced in one of several modes, depending on what the source supports:

-   **Webhook** (when available) – the source pushes changes to PostHog in real time. Fastest freshness, lowest ongoing cost, and the only mode that reliably captures updates and deletes.
-   **Incremental** – only new or updated rows are synced on each run, using a cursor field (such as an `updated_at` timestamp). Cheaper than a full refresh, but deletes aren't captured.
-   **Append only** – new rows are appended using a cursor field; existing rows are never updated. Ideal for immutable, append-only tables like event logs.
-   **Full refresh** – the whole table is reloaded on every sync. Use it when a table has no reliable cursor or when you need deletions reflected.

See [sync methods](https://posthog.com/docs/data-pipelines/sources.md#sync-methods) for a full explanation of how each mode works and how to choose between them.

All Flexmail tables are full refresh. Each sync replaces the contents of the table.

## Configuration

| Option | Type | Required |
| --- | --- | --- |
| `Account ID` | text | Yes |
| `Personal access token` | password | Yes |

## Supported tables

| Table | Description | Sync method | Incremental field | Primary key |
| --- | --- | --- | --- | --- |
| `contact_interest_subscriptions` | One row per contact and interest the contact is subscribed to, joining the contacts table to the interests table. | Full refresh | — | — |
| `contact_sources` | One row per contact and source, recording where the contact's data originated. Every Flexmail contact has at least one source. | Full refresh | — | — |
| `contacts` | A contact in your Flexmail account, with their email address, name, language, and custom field values. | Full refresh | — | — |
| `custom_fields` | A custom field configured for contacts in your Flexmail account (free text, multiple choice, numeric, or date). | Full refresh | — | — |
| `interests` | An interest contacts can subscribe to, used to segment your audience by topic. | Full refresh | — | — |
| `opt_in_forms` | An active opt-in form contacts can use to subscribe to your communications. | Full refresh | — | — |
| `preferences` | A communication preference contacts can subscribe to, such as a newsletter. | Full refresh | — | — |
| `segments` | An active segment: a saved set of conditions grouping contacts for targeting campaigns. | Full refresh | — | — |
| `sources` | A source describing where contacts originated, such as a signup form or import. | Full refresh | — | — |

## Troubleshooting

-   If the connection fails with an authorization error, the personal access token is wrong, expired, or has been revoked. Create a new one, then reconnect the source.
-   If a table syncs no rows, the credential may not have access to that data. Check its permissions, then reconnect the source.

If your sync is failing or data looks wrong, see the [Data warehouse troubleshooting guide](https://posthog.com/docs/data-warehouse/troubleshooting.md). If that doesn't help, [contact support](https://us.posthog.com/#panel=support%3Asupport%3Adata_warehouse%3A%3Atrue) – we're happy to help.