How to Onboard Clients to Your Whitelabel CSS

With your CSS approved and your comparison website live, you are ready to start onboarding clients. This is the step where the investment in setting up your whitelabel CSS begins to pay off. Every client you add generates branded impressions, creates a new revenue line, and strengthens your position as a full-service agency. The onboarding process itself is straightforward and, from the client's perspective, nearly invisible.

This guide covers the technical workflow for switching clients, what clients need to do (very little), what they will notice after the switch, and how to handle the conversation with clients who have never heard of CSS. It also covers bulk onboarding for agencies adding ten or more clients at once.

The Client Onboarding Workflow

The technical process for adding a client to your CSS is simple and follows the same steps every time. Here is the workflow from start to finish:

1. Client provides their Google Merchant Center ID. This is the unique identifier for their Merchant Center account. Most clients already know this number; it is visible in the top-left corner of their Merchant Center dashboard. If you manage their account, you already have it.
2. You submit a CSS switch request through CSS Center. Using your CSS Center account, you submit a request to associate the client's Merchant Center with your CSS. This is a standard process within the CSS Center interface and takes less than a minute per client.
3. Google processes the switch. The switch typically takes 24 to 48 hours to complete. During this period, the client's Shopping ads continue to run normally. There is no interruption in service.
4. Client's Shopping ads display "By [Your Brand]". Once the switch is processed, the attribution on the client's Shopping ads changes from "By Google" (or their previous CSS) to "By [Your Brand]". This happens automatically across all of the client's Shopping campaigns.
5. CPC advantage becomes active immediately. If the client was previously on Google Shopping Europe (the default CSS), they immediately benefit from the CPC advantage that third-party CSS Partners offer. This can reduce effective CPCs by up to 20%, as outlined in our revenue and business model guide.

That is the entire technical process. There is no migration, no campaign restructuring, no feed changes, and no downtime. The client's advertising continues uninterrupted, with the only visible change being the "By" attribution text.

What Clients Need to Do

This is one of the strongest selling points of CSS onboarding: the client needs to do almost nothing. Here is the complete list of actions required from the client:

• Provide their Google Merchant Center ID. That is it for the technical side. If you already manage their Shopping campaigns, you may already have this.
• Approve the switch (in some cases). Depending on the account setup, the client may receive a notification in their Merchant Center asking them to confirm the CSS switch. This is a simple approval click, not a complex process.

There is nothing else the client needs to do. Their campaigns continue running. Their bids, budgets, and targeting remain unchanged. Their product feeds stay exactly as they are. Their Google Ads account is not affected. The switch is invisible from an operational standpoint.

This minimal client involvement makes CSS onboarding significantly easier than most other agency service additions. Compare it to migrating a client to a new advertising platform, restructuring their campaigns, or implementing a new tracking system. CSS onboarding is orders of magnitude simpler.

What Clients Will Notice After the Switch

Once the CSS switch is processed, the only visible change is the "By" attribution on Shopping ads. Here is what changes and what stays the same:

What Changes

• The text below Shopping ads changes from "By Google" (or the previous CSS name) to "By [Your Brand]".
• Clicks on the "By [Your Brand]" link go to your comparison shopping website instead of a third-party site.
• If the client was on Google Shopping Europe, they may see a reduction in effective CPCs due to the third-party CSS margin advantage.

What Stays the Same

• All existing campaigns, ad groups, and product groups remain unchanged.
• Bids, budgets, and bidding strategies are not affected.
• Product feeds and Merchant Center settings stay as they are.
• Performance metrics (impressions, clicks, conversions) continue to accumulate in the same campaigns.
• The client's Google Ads account is not modified in any way.
• Shopping ad placement and ranking are not affected by the CSS switch.

This is a critical point for client communication. The switch is low-risk and non-disruptive. Clients who are nervous about changes to their campaigns can be reassured that nothing in their advertising setup is altered.

The Sales Conversation: Explaining CSS to Clients

Many of your clients will not know what CSS is. That is normal. The concept is not widely understood outside of the agency and e-commerce technology space. Here is a framework for explaining CSS to clients who are hearing about it for the first time.

Start with the Problem

Every merchant running Shopping ads in Europe pays Google a margin on top of their CPC bids. This margin goes to Google Shopping Europe, which is the default comparison shopping service. Most merchants do not know this margin exists because it is built into the auction.

Introduce the Alternative

Since 2017, third-party comparison shopping services can place Shopping ads on behalf of merchants. These services do not charge the same margin as Google Shopping Europe, which means merchants can achieve the same ad placements at a lower effective cost per click. The potential saving is up to 20% on Shopping CPCs.

Explain Your Role

Your agency operates its own CSS. By switching the client to your CSS, they benefit from the CPC advantage, and their Shopping ads display "By [Your Agency Name]" instead of "By Google." There is no change to their campaigns, feeds, or budgets. The switch takes 24 to 48 hours and requires only their Merchant Center ID.

Address the Risk Question

Clients will ask about risk. The honest answer is that there is no operational risk. The switch does not change anything about how their campaigns run. It does not affect their product feeds, their bidding, or their ad placements. If they ever want to switch back to Google Shopping Europe or another CSS, they can do so at any time. The process is fully reversible.

For more detailed sales strategies and objection handling, see our selling CSS to clients guide.

Bulk Onboarding: Adding 10+ Clients at Once

If you are launching your CSS for the first time and want to onboard your existing client base, you will likely be switching ten or more clients simultaneously. The CSS Center supports batch processing, so you do not need to submit individual requests one at a time.

Here is the recommended approach for bulk onboarding:

1. Prepare your client list. Compile a spreadsheet with each client's name, Google Merchant Center ID, and primary market (country). This is the data your provider needs to process the switches.
2. Communicate with clients in advance. Send a brief notification to each client explaining the switch. See the template in the next section. Give clients two to three business days to acknowledge before proceeding.
3. Submit batch switch requests. Through your CSS Center, submit the switch requests for all clients. With Cobiro, you can provide the client list directly and the switches are processed in bulk.
4. Monitor processing. Track the status of each switch in the CSS Center. Most switches complete within 24 to 48 hours. Flag any that take longer for follow-up with your provider.
5. Confirm completion. Once all switches are processed, verify that each client's Shopping ads display the correct "By [Your Brand]" attribution. A quick check in the Google Shopping results for each client's products is the simplest verification.

Bulk onboarding is particularly efficient because the process is identical for each client. There is no customisation or client-specific configuration required. The same switch request applies whether the client has 100 products or 100,000. For guidance on scaling beyond your initial batch, see our scaling to 50+ clients guide.

Client Communication Template

When notifying clients about the CSS switch, keep the communication brief, clear, and focused on the benefit to them. Here is a template you can adapt for your agency:

This template works because it leads with the benefit (lower CPCs), explains the change simply, and reassures the client that no action is needed on their part. You can adapt the language to match your agency's tone and add details specific to your client relationship.

Some agencies choose to include CSS as a new line item on their invoices at this point, while others bundle it into existing service fees. For guidance on structuring your CSS pricing, see our pricing your CSS guide.

After Onboarding: What to Expect

Once your clients are onboarded, the ongoing operational load is minimal. There are no recurring tasks you need to perform for each client. The CSS switch is persistent; clients remain on your CSS until you or they request a change. Product feeds, campaigns, and bidding continue to operate through the client's existing Google Ads and Merchant Center setup.

The main ongoing activities are monitoring your CSS Center for any compliance notifications from Google, adding new clients as your portfolio grows, and managing your billing relationship with clients for the CSS service.

With Cobiro handling the comparison website maintenance, compliance monitoring, and technical infrastructure, your role post-onboarding is focused entirely on the client relationship and business development side. This is what makes whitelabel CSS such an efficient revenue stream: after the initial setup, the time investment per client approaches zero.