B2B marketing without third-party cookies

Are third-party cookies going away?

Not in Chrome. In April 2025 Google said Chrome would keep its current approach, where users choose about third-party cookies in settings, and would not roll out a new standalone prompt.^[1] In October 2025 Google retired most Privacy Sandbox technologies, including Topics, Protected Audience and the Attribution Reporting API.^[2]

So the plan many B2B teams prepared for, a cookie switch-off with Google’s replacement APIs, will not happen. That does not mean tracking is back to normal.

Why is signal loss still real?

Three things still cut what your tags can see, with or without Chrome’s decision:

• Other browsers block cross-site tracking. Safari has blocked cookies for cross-site resources by default since 2020.^[3] Firefox keeps each site’s cookies in a separate jar by default on desktop, so trackers cannot follow a visitor between sites.^[4]

• Consent decides what tags may store. Where the law requires consent, a visitor who declines analytics or ads is not tracked with cookies at all.

• Corporate networks block trackers. Many company browsers and security tools block ad and analytics scripts, and your best prospects often sit behind them.

For B2B the effect is larger than the share of affected visitors suggests. Volumes are small, cycles are long and one lost conversion can be a lost opportunity.

How does consent mode help?

Consent mode passes each visitor’s choice to Google tags, which then adjust what they do.^[5] It has four signals: ad_storage and analytics_storage for cookies, ad_user_data for sending user data to Google for ads, and ad_personalization for remarketing.^[5]

There are two ways to run it.^[5]

• Basic: tags stay blocked until the visitor answers the banner. If they decline, nothing is sent.

• Advanced: tags load with consent denied by default and send cookieless pings until consent is given. Google Ads and Google Analytics use these pings to model conversions, once your traffic passes a privacy threshold.

Whichever mode you choose, the consent banner and the tags must agree. A banner that says “reject” while ad tags still fire is a legal risk, not a measurement trick.

What should replace cross-site signals?

First-party data you collect with permission. For B2B that means:

• Known visitors, not anonymous ones. Ask for a work email on your most useful assets, such as guides, calculators and benchmarks, and keep forms short. Collect one more detail at each later visit instead of everything at once.

• Account-level views. Join form fills, email clicks and event sign-ups to the account in your CRM, so two people from one company show up as one account.

• Context instead of tracking. Ads on trade publications and pages about your category reach buyers while they research, without following anyone between sites.

How do conversions reach ad platforms?

From your own systems. Enhanced conversions for Google Ads send hashed first-party data, such as an email address, with each conversion so Google can match it to signed-in accounts.^[7] Meta and LinkedIn run their own conversions APIs for server and CRM events. Our guide to closing the loop from CRM to ad spend covers each one.

Server-side tagging helps here. Data goes to a server container you control first, and you decide what is shaped and sent to each vendor.^[6] It does not remove the need for consent: the server container should read the consent state and drop ad data when it is denied.

Data clean rooms are the next step for teams that want to compare their customer list with a platform’s audience without sharing raw records. See data clean rooms for advertising.

How should B2B teams measure?

Expect fewer user-level paths and plan for aggregates:

• Marketing mix modeling to read channel effect from spend and outcomes over time. MTA vs MMM explains when each fits.

• Incrementality tests such as geographic holdouts or switching a channel off for a period.

• Self-reported attribution, a “How did you hear about us?” field on the booking form.

Browser-level measurement may return as a standard. After retiring the Attribution Reporting API, Google pointed to work on an interoperable attribution standard in the W3C Private Advertising Technology Working Group.^[2] That group publishes Attribution Level 1, still a working draft for an API that reports aggregate, privacy-protected ad statistics.^[8] Treat it as something to watch, not something to plan budgets on.

Where should a B2B team start?

1. List every tag on your site and what it stores, and check that each one respects the consent banner.

2. Turn on consent mode and decide between basic and advanced with your legal adviser.

3. Capture a work email and the ad click ID on every form, and keep both in the CRM.

4. Send qualified opportunities back to your highest-spend platform, then add the others.

5. Add one aggregate method, such as a holdout test, before the next budget review.

Our analytics and attribution service covers these steps as part of our B2B demand generation work.