Tomorrow Google closes a door that many advertisers don't even know is open.
Starting June 15, 2026, Google is blocking new developer tokens from uploading offline conversions via the Google Ads API. The specific methods being cut off are UploadClickConversion and enhanced conversions for leads uploads. And developer tokens that haven't sent offline conversion requests between January and June 2026 won't be allowlisted for legacy access either — even if they were active before.
The new required path for all new setups: the Data Manager API.
What offline conversions actually do for your campaigns
For most paid media managers, offline conversions is the mechanism that connects real business outcomes to the click that started them. A shopper sees your search ad, calls your sales team, and signs a contract three weeks later. That closed deal gets uploaded back into Google Ads and credited to the original click — so Smart Bidding knows which search queries are generating actual revenue, not just form fills.
This is the signal that separates bidding on proxies from bidding on results. Without it, a target CPA campaign optimizes toward whatever conversion event is still flowing, typically the top-of-funnel ones.
Brands that depend on offline conversions include:
- Lead gen operations feeding CRM data (Salesforce, HubSpot) into Google Ads
- E-commerce brands with phone-order pipelines or in-store purchase data
- B2B advertisers using enhanced conversions for leads with hashed contact data
- Agencies running conversion integrations through Zapier or custom-built pipelines
Who is actually at risk tomorrow
The change has two distinct layers and they affect different advertisers.
The first is obvious: any new implementation of offline conversion imports must use Data Manager API from June 15 onward. If you or a developer is trying to set up offline conversion uploads for the first time, the old Ads API method simply won't work. This means any third-party CRM tool that hasn't updated its integration is now delivering a broken setup out of the box.
The second layer is less visible. Developer tokens that were never used — or went quiet — between January and June 2026 will not be allowlisted for legacy access. If your offline conversion pipeline was configured years ago but the integration stopped sending data at some point over winter, the token may no longer be grandfathered.
Your campaigns keep running either way. Google doesn't send a warning email when a conversion import pipeline goes silent. Smart Bidding adapts to whatever data is available.
The part that makes this expensive
Smart Bidding doesn't fail loudly when conversion data disappears. It adapts — which usually means defaulting toward the conversion actions still reporting. If your pipeline was sending closed-deal data and that signal goes dark, the algorithm shifts toward form fills without telling you.
What you see in the dashboard: stable ROAS, similar conversion volume.
What's actually happening: the platform is bidding on proxy events while the downstream business signal has gone quiet.
The gap between Google Ads ROAS and actual revenue is where this plays out. Most advertisers don't notice until they reconcile campaign spend against CRM data weeks later.
How to check before the deadline hits
You don't need API access to do this audit.
In Google Ads, navigate to Goals → Conversions → Summary. Filter for conversion actions where the source reads "Imported from clicks" or "Imported from calls." Check the "Last conversion" date column. If you're seeing timestamps from weeks or months ago, something in the pipeline has already broken — the June 15 change didn't cause it, but it will prevent any fix that requires the old API method.
Then ask your integration tool or CRM provider one direct question: does their Google Ads connection use the Google Ads API for conversion uploads, or have they migrated to Data Manager API? The major platforms (HubSpot, Salesforce, Zapier, and most agency tech stacks) will either have a published migration status or be able to answer directly.
If the answer is "we use the Ads API" and their token hasn't been active, you have until tonight.
What stays the same
If your offline conversion pipeline has been running consistently — sending data through an active developer token between January and June 2026 — you're almost certainly grandfathered for now. Google is not forcing an immediate migration of existing active setups. But the direction is clear: Data Manager API is where all conversion infrastructure is consolidating. Legacy Ads API access will end at some point, and every agency or tool transition, CRM swap, or developer token rotation will hit this wall.
Setting up correctly today means not rediscovering the problem during a budget push when a new integration fails silently.
Smart Bidding quality is a direct function of conversion data quality. If you've built a performance campaign on offline signal, run the check before tomorrow.
If you want to see where your conversion setup is exposed, Gromerce's free account audit flags silent measurement gaps in about three minutes.
Your bids are only as smart as the data behind them.
Sources: Google Ads Developer Blog, PPC Land, Techwyse, Search Engine Land, June 2026
