Offline conversions with the Meta API: closing the loop between the physical and digital world 

As brands seek to understand in the digital world the impact of every euro they invest, in every action and on every platform, they are also pursuing and facing another major challenge: How do you accurately measure conversions that happen outside the digital environment, such as an in-store purchase or a closed sale over the phone? 

To what extent does that digital investment actually influence the conversions that occur offline?

Until very recently, Meta offered a solution to this challenge through its Offline conversions APIa tool that allowed physical sales data to be linked with advertising campaigns in Facebook and Instagram. It allowed advertisers to close the loop between the online and offline environment, thereby optimising their attribution and performance.

However, Meta has announced a major change to its measurement ecosystem, ending the offline conversions API. As an alternative, Meta recommends migrating to its API Conversion (NITAG)which now also allows for unified offline event submission.

Therefore, if your brand currently uses the Offline conversions APIIf you're looking for a way to improve your measurement strategy, it's essential that you update your measurement strategy as soon as possible. In this article we explain in detail what they are. offline conversionshow to leverage this technology for your SEM campaigns, and how to prepare you for a successful transition to the new Meta API.

What are conversions?

In digital marketing, a conversion represents a key action within the sales funnel, such as a purchase, a lead generated or a booking. While most are measured across digital platforms (web, app, e-commerce), many companies - especially those with offline sales processes - face the challenge of correctly attributing conversions that are completed outside of the online environment.

What is an offline conversion?

An offline conversion is a conversion that occurs outside the digital environment, after a user has previously interacted with an online campaign. Some common examples:

• A user sees an ad on Instagram, visits the physical shop days later and makes a purchase.

• A person completes a contact form after seeing an advertisement, but the sale is closed weeks later over the phone.

• Someone interacts with a Facebook Ads campaign and then schedules a doctor's appointment via WhatsApp, who becomes a patient after the face-to-face consultation.

In all these cases, digital advertising influences the decisionbut the final conversion occurs off the radar of traditional analytics tools.

Online vs. offline conversions

In short, although online conversions are easier to measure and optimise, offline conversions account for a large part of revenue for many businesses. Ignoring them can lead to decisions based on incomplete data and thus to a loss of real opportunities or an incorrect allocation of investment.

That is why it is so important to integrate both into your measurement strategy.

What is the Meta Offline Conversions API?

The Meta Offline Conversions API is a tool that allows advertisers to send conversion data that occurs outside of the digital environment (such as in-store sales, phone calls or face-to-face bookings) directly to Meta's servers. This allows these actions to be attributed to advertising campaigns running on platforms such as Facebook and Instagram.

Through this API, companies can close the measurement loop and have a more complete view of the real impact of their advertising spend, even when sales do not occur online.

Key details:

• Deadline for uploading data: You can send transaction data up to 62 days after conversionThis allows you to attribute offline sales even when they occur some time after the interaction with the ad. 
• Type of information you can include: It is possible to provide data such as: Exact time of the event (timestamp); Product details (such as product_id, order_id, quantity, price, currency); Customer information (email, phone and other profile data such as first name, last name, city, date of birth)-all hashed to comply with privacy and facilitate cross-referencing with users who viewed or clicked on the advertisement. 
• Attribution window: Meta uses a window of 28 days to attribute offline conversions to your ads.
• Duplication window: 7-day window to avoid duplicate counts

Why is it important for SEM campaigns?

The integration of offline conversions with Meta allows:

• Better optimise the algorithm: allows you to understand what type of users are generating real results, thereby improving targeting and campaign performance.
  
• More accurate measurement: allows you to make decisions based on real data and not just on superficial metrics such as clicks or form completions.
  
• Automation and scalability: the API allows data to be sent automatically, without manual processes or additional tools.
• Fairer attribution: Many offline sales originate from digital campaigns. Without this connection, those conversions are not attributed correctly, which could lead you to pause campaigns that are actually working.

How to implement the API and send the offline conversions to the meta servers

Before I show you the step by step, you must have a CRM, ERP or backend system in place that allows you to export conversion data and also ensure that you comply with privacy regulations (e.g. GDPR). Data should be sent hasheados (SHA256).

Step by Step

Create a set of offline events

• In the Event ManagerSelect the existing dataset and click on "add events". Then click on "add events to a new integration".
• Link your advertising account.

Configure permissions

• Ensure that the user or system that will send the data has appropriate permissions on the event set.

Preparing the data

• The file must include:
  • Date/time of the event
    
  • Customer data (email, telephone, name, etc.)
  • Conversion information (amount, product, currency)
    
• Encrypt personal data using SHA256 (some platforms such as Zapier, HubSpot or CRMs do this automatically if you set up the integration correctly).

Send data via API

• You can use:
  
  • Direct integration by code (via HTTP POST)
    
  • Third-party tools (e.g. Zapier, HubSpot, Segment)
    
• Base URL: https://graph.facebook.com/v{version}//events (this is the address to which your system should make the HTTP POST request with the data (name, email, conversion date, value, etc., already entered). Meta will receive this data, process it and relate it to your ad campaigns).

Check and clean

• Check for errors or warnings in the Event Manager.
• Use the Test Event Tool to validate submissions before uploading actual data.

Automate: Once the flow has been verified, schedule regular (daily or weekly) mailings from your CRM or internal system.

Below you will find the Meta's official resources so that you can have more detailed information:

Conclusions

In a increasingly hybrid ecosystemwhere purchasing decisions constantly cross the boundaries between the online and offlineaccurate measurement is more necessary than ever. Integrating offline conversions into Meta not only improves attribution, but allows you to optimise campaigns with a complete view of the user journey.

Although the Offline conversions API will cease to be available, the transition to the new Conversion API offers a unified, flexible and robust solution. Adapting to this change is not just a technical issue, but a competitive advantage for data-driven decision-makers.