On January 11, 2027, a default flips inside a piece of infrastructure most marketing teams paid for and almost nobody on those teams has opened. If you run Google’s advertising tags through a server-side Tag Manager container, those tags start receiving your visitors’ full IP addresses that day. Not shortened. Full. Nobody has to click anything for that to happen. Keeping things the way they are today is the part that takes work.
That work is a small build, a test, and a publish. It is also a decision about what your company has promised its customers, and it is due in the worst stretch of the year to get anything shipped. From today it is 60 days away. A good chunk of those days are Black Friday, Cyber Monday and, at any company that runs a holiday change freeze, weeks when site and tag changes stop altogether.
So the useful question for this week is not whether full IPs are good or bad. It is who decides, and whether they decide before the calendar decides for them.
What Google actually told people
The change arrived as an email, not a blog post. Google Ads consultant Adriaan Dekker posted it on LinkedIn on November 2, and Search Engine Journal (November 3) quoted it in detail. The notice is titled “Updates to network signal processing in server-side tagging” and carries no issue date. It says server containers “will transition from container-wide IP address redaction to individual tag-level processing” and lists four effects. Tags sending data to Google Ads, Display & Video 360, Search Ads 360 and Campaign Manager 360 “will now accept the full IP address.” Google Analytics tags keep redacting. Third-party tags keep their own rules. And Transformations, a server container feature that edits event data before tags read it, “can redact these signals before any tag accesses the data.”
The same date and the same four effects show up in independent write-ups from MACCUS (November 5) and Relevant Audience (November 4). Google’s stated reasons are that the change will “facilitate improvements to Ads measurement and personalization,” that it “integrates privacy-enhancing technologies,” and that it helps filter spam and invalid traffic. MACCUS points out that Google named none of those technologies and attached no numbers to the performance claim. As of those reports, the change was not in the Tag Manager release notes either.
Read that list again from a buyer’s seat. Campaign Manager 360 is where Floodlight lives. Search Ads 360 is where a lot of big retail search money is managed. Display & Video 360 is the programmatic seat. This is not a niche developer story. It touches the conversion tags that feed the bidding you are about to lean on hardest.
There is no switch. There is a build.
Google’s opt-out is documented on a Tag Manager Help page titled IP address redaction for server-side tagging (undated, read November 12). It is a recipe, not a setting. Someone creates a custom template variable that calls a function named getAnonymizedIpAddress, creates an “Augment event” transformation that overwrites the ip_override field with that variable, picks which tags it applies to, previews it, and publishes the container. The page does not mention January 11 at all. As PPC Land (November 12) put it, the date and the default still rest on the email alone.
The analytics consultancy TRKKN, quoted in that PPC Land piece, said it plainly: “There is no simple switch.” Its advice is to publish the transformation before January 11 to avoid a gap and to test it in December.
What the function does is precise. Google’s server-side tagging API reference (page updated November 9) says it sets the last octet of an IPv4 address to zero and keeps only the first 48 bits of an IPv6 address. If the address is invalid it returns a safe blank value. Search Engine Journal found the function was missing from an October 12 archive copy of that same reference page, which tells you how new the official path is.
Three details in the fine print are where teams will trip.
First, scope. A transformation pointed at named tags covers only those tags. PPC Land notes that a Google advertising tag added to the container later would go out with the full address unless someone remembers to add it to the scope, and that transformations have been able to target whole tag types since 2023. If you build this, build it so the next tag added in a rush in Q1 does not quietly bypass it.
Second, other vendors. Google’s help page says many third-party tag templates read the IP from the same ip_override field and will inherit the fix. Not all do. Some read it from custom headers or event parameters, and those need their own transformation aimed at the exact field. If you route Meta, TikTok or a retail media pixel through the same container, somebody has to check each one rather than assume.
Third, the question Google has not answered. Server containers already carry traffic from people who said no to advertising cookies. Since July 28, 2025, Floodlight tags in server-side Tag Manager have sent unconsented requests server to server for conversion modeling, as Search Engine Journal and PPC Land both note. Will those requests carry the full IP after January 11? Google has not said. TRKKN told PPC Land it does not know either and recommends keeping the address redacted for anything sent without consent. That is the single most important open question in the whole change, and it is the one most likely to be asked by your lawyer after the fact rather than before.
Why this is a marketing problem and not just a tagging ticket
Marketing usually owns the server container budget, even when an agency or a contractor owns the keyboard. Server-side tagging got sold internally on two promises: better measurement in a world of browser restrictions, and more control over what each vendor receives. The second promise is the one that changes on January 11. Protection that used to apply once across the whole container becomes something you have to configure tag by tag and keep configured.
That puts three people in the same room who do not normally talk about Floodlight.
The growth lead, who will hear Google’s pitch that fuller signals mean better measurement and invalid traffic filtering, and who may want that, especially after a year of fraud stories. That is a legitimate choice. It just has to be a choice.
The privacy or legal lead, who needs to know whether anything your company has written says IP addresses are shortened before they reach Google. TRKKN flagged exactly this check. If your privacy notice or your internal records of processing say that, they become untrue for those four ad products on January 11 unless the transformation is live. PPC Land adds a wrinkle worth putting in front of counsel: in Google’s own data protection paperwork, Google Ads sits in a list of products where Google acts as a controller in its own right, not in the processor table that covers Tag Manager and the other three. That is PPC Land’s reading of Google’s terms, not a ruling, but it is a question your counsel should answer, not your tag manager.
The person who actually ships changes to the site, who is about to tell you the window closes soon.
And this is not the only IP default moving. Google’s Analytics data controls page (read November 12) says IP addresses automatically collected by the Google tag and SDK “will be encrypted and flow to your linked Google Ads account,” with dates to be shared later this year. One change is dated and one is not. Treat them as one conversation with legal rather than two surprises.
The holiday calendar is the real deadline
Sixty days sounds like plenty. Count it the way an engineering lead counts it. Take out Thanksgiving week and Cyber Week. Take out whatever freeze your company runs on site and tag changes through peak, if it runs one. Take out the last two weeks of December, when the people who know how the container was built are on leave. What is left is a few working days now and a few in early January, right before the date.
Publishing a server container on January 8 and hoping nothing breaks is not a plan. A mis-scoped transformation can break more than privacy. It edits the event data your conversion tags read, and conversion tags are what your bidding learns from. Nobody wants to discover in the second week of January that a Floodlight tag stopped firing cleanly and Smart Bidding has been working from thin data for days.
The sensible move is boring. Make the decision this month, build and test before your freeze starts or in an approved window, and spend early January confirming rather than building.
If you decide to let full IPs through
You might. Google’s argument is better measurement, personalization and invalid traffic filtering, and some advertisers will reasonably want every signal they can feed the machine. If that is your call, make it on paper. Update the privacy notice and records so they describe what actually happens. Confirm consent covers it, especially for any traffic from the European Economic Area, the UK or Switzerland, where Google’s EU User Consent Policy applies and where the notice puts the duty for consent on you, not Google. Get a written answer on unconsented requests before you accept the default for them.
Then annotate January 11 in every report that leans on Google conversion data. Google has given no figures for what fuller signals will change, so you cannot predict a lift or a drop. You can make sure that if the numbers move that week, nobody spends February attributing it to creative.
What to do this week
Find out whether you are in scope at all. Ask your analytics lead or agency one direct question: do we run a server-side Tag Manager container, and does it hold Google Ads, Floodlight, Search Ads 360 or Display & Video 360 tags? If the answer is Analytics only, or no server container, you are outside this change as Google described it. Write that down and move on.
If you are in scope, name one owner for the decision and one for the build. They can be the same person. They cannot be “the agency” in the abstract.
Make the call per tag: full IP or partially redacted. For anything sent without consent, default to redacted until Google says otherwise in writing.
Send legal the privacy notice question this week, with the exact sentence from your notice that mentions IP addresses, if there is one. Add the Analytics change to the same email so it is one review.
Ask your Google rep, in writing, two things: whether consent-denied requests in server containers will carry the full IP after January 11, and where those addresses are stored and for how long. Search Engine Journal noted the notice is silent on storage too.
Book the build into a real window. If your freeze starts before Thanksgiving, that means the next two weeks. Scope the transformation by tag type so future tags inherit it, check each third-party tag’s IP field, preview, and publish.
Put a check on the calendar for January 12: confirm conversion tags are firing, conversion volumes look normal against the prior week, and the redaction is doing what you think it does.
Agencies, this is worth a short note to every client with a server container this week. It is a fixed date, a documented fix, and a privacy question that lands on the client. Being the one who raised it in November is a lot better than being the one who explains it in January.
The deeper point is one this year keeps making. More of what used to be protected by default now has to be protected on purpose. A server container that nobody has opened since the day it was set up is still making decisions for you. From January 11, one of those decisions is what it tells Google about every visitor.
