How to Set Up Offline Conversion Tracking in Google Ads

Your Google Ads campaigns drive traffic. But if your actual sales happen offline—phone calls, in-store purchases, email inquiries—Google Ads doesn't see them. That gap means your campaigns optimize for clicks, not revenue. Offline conversion tracking (OCT) closes that gap by feeding real sales signals back into Google Ads so the system learns which ads, keywords, and audiences actually generate high-value outcomes.

Without OCT, you're flying blind. Your conversion rate looks artificially low. Your return on ad spend (ROAS) appears worse than it is. Google can't optimize toward your best customers. Setting up OCT takes a few hours upfront but unlocks months of better-informed bidding and targeting.

This post covers how to configure OCT, match customer data, and troubleshoot common setup mistakes.

What Offline Conversion Tracking Does

OCT lets you upload conversion data (sales, leads, phone calls) that happened outside Google Ads, then match that data back to the original ad click. When a match is found, Google Ads treats it like any other conversion: it updates your conversion rate, feeds the signal into Smart Bidding, and helps the system understand which campaigns, keywords, and audiences drive real business outcomes.

The process works in steps. A customer clicks your ad. Google stores a click ID (gclid) for that click. Later, your CRM, point-of-sale system, or call tracking software records the sale and captures the customer's email or phone number. You then upload that conversion data to Google Ads with the customer's email or phone, and Google matches the email/phone to the original gclid. If the match succeeds, the conversion is attributed.

This is different from online conversion tracking (where a pixel fires on your website). OCT is for sales that never touch your website, or for high-value transactions where you want to report the actual deal value instead of a generic "form submission."

Prerequisites and Data Requirements

Before you set up OCT, confirm you have the right data sources and structure in place.

You need a way to capture customer contact information at the point of sale. If a customer calls your business, your call tracking system must record the phone number. If they buy in-store, your point-of-sale system must capture their email or phone. If they complete a sales call after an inquiry, your CRM must log the email address. Without this data, you have nothing to upload.

You need the conversion value and date. OCT requires at least the date the conversion happened and the customer's email or phone number. Conversion value (the sale amount) is optional but strongly recommended for high-value businesses. Google Ads uses value to calculate ROAS and to weight conversions in Smart Bidding.

You need access to Google Ads account settings. Only users with Admin or Editor access can set up OCT. If you don't have this level of access, ask your account owner or manager.

Customer data must be hashed. When you upload conversion data, emails and phone numbers must be hashed using SHA256 before they leave your system. Google does not accept raw emails or phone numbers for security and compliance reasons. Most modern CRM and data platforms handle this automatically, but verify with your vendor.

Step 1: Enable Offline Conversions in Google Ads

Start in your Google Ads account. Go to Tools and settings (wrench icon, top right) and select Conversions under the Measurement section. Click the blue + Conversion button and choose Import (not "Website" or "App").

Select Offline or CRM system as the data source. Give the conversion a clear name (e.g., "Phone Lead" or "In-Store Purchase"). Set the conversion category to match the type of sale (Lead, Purchase, or other). Choose a conversion value if your sales have variable amounts; if all conversions are worth the same, you can set a fixed value here.

Set the conversion window (how long after the ad click a conversion can be attributed). The default is 30 days, which works for most businesses. If your sales cycle is longer (e.g., B2B enterprise sales take 60 days), extend this window. Longer windows capture more conversions but also introduce more noise if customers take a very long time to decide.

Click Create and continue. Google will generate a Conversion ID and a Conversion Label. Save both. You'll need these to upload data later.

Step 2: Choose Your Data Upload Method

Google Ads supports three ways to send offline conversion data: the Google Ads API, Google Sheets (for one-time or manual uploads), or a third-party CRM integration.

Google Ads API: Best for high-volume, automated uploads. Your CRM or data platform connects directly to Google Ads and sends conversion data in real time or batch. This requires technical setup but is the most scalable and reliable method. If your CRM is Salesforce, HubSpot, or another major platform, it likely has a native Google Ads integration.

Google Sheets: Best for manual, one-time, or low-volume uploads (under 100 conversions per month). You fill in a spreadsheet with customer emails/phones, conversion dates, and values, then upload it through Google Ads. This is simple but not scalable and prone to human error.

Third-party integrations: Platforms like Zapier, Make, or native integrations (Salesforce, HubSpot, Klaviyo) can push data to Google Ads automatically. Check if your CRM has a built-in Google Ads connector; if so, use it instead of manual uploads.

For most businesses, automated API or CRM integration is the right choice. Manual uploads work only if you have fewer than 10–20 conversions per week and can tolerate a 1–2 day delay in attribution.

Step 3: Prepare and Hash Customer Data

Before uploading, you must hash customer contact information. Hashing converts an email or phone number into an irreversible string of characters. Google cannot reverse the hash to see the original data, but Google can hash the same email/phone on its end and compare the hashes to find matches.

Most CRM platforms and data warehouses hash automatically. If you're uploading via Google Sheets or a custom script, you must hash manually. Use a SHA256 hashing tool or your programming language's built-in hash function.

For phone numbers, normalize first (remove spaces, dashes, country codes). For example, convert "+1 (555) 123-4567" to "5551234567" before hashing. For emails, convert to lowercase and remove leading/trailing spaces. Google is strict about formatting; a single space or character difference breaks the match.

If you're unsure whether your CRM is hashing correctly, test with a known email address. Upload a conversion with your own email, and check if Google Ads reports a match within 24 hours.

Step 4: Upload Your First Batch of Conversions

Go back to Tools and settings > Conversions and find your offline conversion. Click on it and select Upload conversions.

If you're uploading via Google Sheets, click Download template. The template includes columns for hashed email, hashed phone, conversion time, and conversion value. Fill in the data (one conversion per row) and re-upload the file. Google processes the file within 24 hours.

If you're using the API or a CRM integration, the upload happens automatically on a schedule you set (hourly, daily, or weekly). Verify in your CRM's settings that the integration is enabled and that the Conversion ID and Conversion Label are correctly entered.

Start with a small test batch (10–20 conversions) to check for errors before uploading thousands of rows. Look for formatting issues, missing data, or hashing mistakes.

Step 5: Verify Matches and Monitor Attribution

After 24–48 hours, return to the offline conversion in Google Ads and check the Match rate. This shows the percentage of uploaded conversions that Google successfully matched to ad clicks.

A match rate of 40–60% is typical for most businesses. A rate below 30% suggests a data quality issue (mismatched emails, wrong conversion window, or customer data not captured at the point of sale). A rate above 70% is excellent and means your data is clean and your conversion window is appropriate.

If your match rate is low, check these common issues.

• Customer email or phone not captured: If your sales team or point-of-sale system doesn't collect customer contact info, Google has no data to match. Add a step to capture this at every sale.
• Conversion window too short: If customers take 45 days to convert but your window is 30 days, matches are missed. Extend the window in your conversion settings.
• Hashing errors: Spaces, capitalization, or formatting differences in emails/phones prevent matches. Re-verify your hashing process.
• Mismatched customer data: The email uploaded might not match the email Google has on file from the original click. This is rare but can happen if the customer used a different email or device.

Once match rates stabilize, monitor your conversion volume in the Conversions column in your campaign reports. You should see conversions flowing in regularly. If conversions suddenly drop to zero, check that your upload process is still running and that data is still being captured correctly.

Step 6: Link Offline Conversions to Smart Bidding

After OCT is running and match rates are stable, update your bidding strategy to use the offline conversion. Go to your campaign or ad group, click Bidding, and select a Smart Bidding strategy (Target CPA, Target ROAS, or Maximize Conversions).

In the conversion selection, choose your offline conversion (not just website conversions). Google Ads will now optimize bids based on the full picture: both online and offline conversions.

If you have both online and offline conversions, you can use conversion value rules to weight them differently. For example, if an online form submission is worth $50 but an offline sale is worth $500, you can set different values so Smart Bidding prioritizes the higher-value offline conversion.

Common Setup Mistakes to Avoid

Forgetting to normalize phone numbers before hashing is a frequent error. A phone number with a country code (+1) hashes differently than one without. Standardize all phone numbers to the same format (e.g., 10 digits, no country code for US numbers) before hashing.

Uploading conversions with a conversion window that's too short causes match rates to plummet. If your typical sales cycle is 45 days, set your conversion window to at least 60 days. You can always shorten it later if you see too much noise.

Not capturing customer contact information at the point of sale defeats the whole setup. If your sales team doesn't ask for an email or phone, or your point-of-sale system doesn't store it, you'll have nothing to upload. Make it part of your sales process before you set up OCT.

Uploading the same conversion twice (once from your CRM and once manually via Google Sheets) inflates your conversion count. Choose one upload method and stick with it. If you switch methods, pause the old one first.

Assuming all conversions are online. OCT is specifically for offline sales. If a customer fills out a form on your website and completes a purchase online, that's an online conversion and should be tracked with a website pixel, not OCT. OCT is for sales that happen outside your website.

Reality Check: Timing and Scope

Expect setup to take 2–4 hours if your CRM already captures customer contact data and has a Google Ads integration. If you need to build a custom data pipeline or modify your sales process to capture emails and phones, add 1–2 weeks.

Match rates stabilize after 1–2 weeks of data uploads. Don't adjust your bidding strategy or conversion window in the first week; give Google time to accumulate enough data to optimize.

OCT is not a replacement for online conversion tracking. If you have a website, set up both. OCT captures offline sales; website pixels capture online behavior. Together, they give Google the full picture.

OCT does not work retroactively. You can only match conversions to clicks that happened after OCT is enabled. Historical sales cannot be matched to old ad clicks.

What to Do Next

If your CRM or point-of-sale system already has a native Google Ads integration, enable it in your CRM's settings and test with a small batch of conversions. If not, contact your CRM vendor or a Google Ads specialist to build an API connection or evaluate third-party platforms like Zapier or Make.

Verify that your sales process captures customer email or phone at every transaction. If not, update your process now before you enable OCT. The quality of your data determines the quality of your attribution.

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