Google Ads for ecommerce: strategy, campaigns, budget

Google Ads for ecommerce is the channel that brings many stores revenue fastest, and also the one where money disappears fastest. The difference is rarely the ad creative. It is measurement, account structure, and knowing which campaign type has which job. This guide walks from the prerequisites through structure, bidding and budget maths to a concrete plan for your first 90 days.

What Google Ads for ecommerce needs before you spend anything

1. Conversion tracking that carries values

Google Ads needs more than the information that an order happened. It needs the revenue per order, otherwise no value-based bidding strategy can do its work.

Check specifically:

• There is a conversion action for the purchase, it is set as a primary conversion, and it passes a dynamic value.
• Secondary goals such as newsletter signups or add-to-cart are marked as secondary conversions so they do not feed bidding.
• The purchase is counted once, not twice. Importing purchases from GA4 while also running your own tag is a common cause of double counting.
• Enhanced conversions are switched on so more purchases can be attributed.

If your numbers already look wrong at this stage, fix that first. The article on finding missing purchases in GA4 ecommerce tracking covers the usual failure points, and why Shopify revenue and GA4 rarely match exactly explains which gaps are normal and which are not.

2. Merchant Center with approved products

For stores, a large share of advertising runs on product data. That means a Merchant Center account, a verified and claimed website, and a feed whose items carry the status approved. Disapproved products cannot be advertised, no matter how well the campaign is built. The full walkthrough is in Google Merchant Center setup.

3. Links between the accounts

Merchant Center and Google Ads have to be linked. Link GA4 and Search Console too, so you can judge paid and organic visibility side by side instead of in separate tabs.

Campaign types and the job each one does

Two rules go with that table.

Capture demand before you create it. If you do not yet have a campaign responding to existing searches, do not put budget into reach.

Separate what you want to judge separately. Search and Performance Max overlap on brand queries. If you run both, you need a rule for that overlap: a dedicated brand search campaign plus brand exclusions in Performance Max. How to keep control inside an automated campaign is covered in Performance Max for ecommerce.

Account structure: as few campaigns as you can get away with

The most common structural mistake in store accounts is fragmentation: twenty campaigns at $5 a day, none of them with enough conversions to learn from. Build your structure around the decisions you want to make, not around your shop navigation.

Splits that earn their keep:

• By target value. A product line with a 15 percent margin and one with 60 percent need different ROAS targets, so they need different campaigns.
• By country and language. Separate campaigns, otherwise clean evaluation is impossible.
• Brand versus non-brand. Brand queries are cheap and convert well. Mixed in with everything else, every campaign looks better than it is.
• By stock logic. Clearance or end-of-season stock that has to move deserves its own campaign with its own target.

Splits that only cost you data: one campaign per product, one keyword per ad group in a small account, a separate campaign for every subcategory that sells two units a month.

Inside a search campaign

Group ad groups by search intent, not by SKU: one group for "women's running shoes" and its close variants, another for "women's trail shoes". One responsive search ad per ad group with the fields largely filled, plus assets: sitelinks, callouts, structured snippets, images.

Use broad match only with maintained negatives. In the first weeks the search terms report is your most important report, because it is the only place that shows what you actually paid for. Read it twice a week and exclude what does not belong.

Bidding strategies: what fits when

For stores, maximize conversion value is the destination. The route there: start with maximize clicks and a max CPC until conversions come in steadily, switch to maximize conversion value without a target, and only then set a target ROAS. An over-ambitious target from day one means the campaign never spends its budget and never collects data.

Change target values in steps of roughly 10 to 20 percent, then wait one to two weeks. Every large change restarts the learning period.

Working out your budget and ROAS target

Budget follows from your own maths, not from a benchmark. You need two figures: the margin left after all variable costs, and what a customer is worth over time.

Worked example, for illustration only. Average order value $80 excluding tax, cost of goods $40, shipping and packaging $6, payment fees $2. That leaves $32 gross margin, or 40 percent. Break-even ROAS is therefore 80 / 32 = 2.5. If you want to earn $12 per order, advertising may cost at most $20, which is a ROAS of 4.

The allowed cost per order gives you the budget: 60 additional orders a month multiplied by $20 allowed ad cost equals $1,200 a month. The method behind this, including when it is rational to pay more for a first order, is in how to calculate ROAS.

How the daily budget actually works

The field is called average daily budget for a reason. Google describes the mechanics in its help page on the average daily budget:

• On any single day, the daily spending limit for most campaign types is twice the average daily budget, so a busy day can cost double.
• Over a month, the monthly spending limit is average daily budget × 30.4, the average number of days in a month. At $50 a day that is about $1,520 a month.
• If more is delivered than those limits, Google does not charge you for the excess.

Two practical consequences. First, do not panic about one day with double the cost; the monthly total is the number you plan with. Second, when you derive a daily figure from a monthly budget, divide by 30.4, not 30.

And one budget mistake that has nothing to do with mechanics: a budget spread so thinly across campaigns that none of them produces meaningful conversion counts is the most expensive form of thrift there is. As an experience value, not a Google requirement, a campaign on a value-based strategy wants 15 to 30 conversions a month before its numbers mean anything.

The landing page decides too

No campaign rescues a weak page. Before launch, check:

• Does the click land on a matching category or product page rather than the homepage?
• Are price, availability, shipping cost and delivery time visible without scrolling?
• Does the page load fast on mobile? Ad clicks are paid traffic, so every second costs real money. The thresholds worth hitting are in Core Web Vitals for online stores.
• Is the path to the cart short, does it work on a phone, are payment methods visible?
• Do ad copy and page agree? If the ad promises free shipping over $50, the page has to repeat it.

If a lot of clicks drop out before the cart, that is not an Ads problem. It is a store problem, and more budget will not improve it.

A 90-day plan

Days 1 to 7: measure and prepare

1. Verify the purchase conversion action passes a dynamic value, enable enhanced conversions, remove secondary goals from bidding.
2. Place a test order and confirm in the account that it arrives with the correct value.
3. Check Merchant Center: feed current, products approved, prices and availability matching the store.
4. Link Merchant Center to Google Ads, connect GA4 and Search Console.
5. Calculate margin and allowed cost per order, then set the budget.
6. Set account basics: location option to presence rather than presence or interest, languages matching your pages, and a deliberate decision on search partners and Display in search campaigns.
7. Build an account-level negative keyword list: free, used, second hand, repair, tutorial, jobs, plus competitor names you do not want to serve.

Days 8 to 30: launch with two campaigns

8. Brand search campaign. Small budget, its own campaign, so brand cost stays visible separately.
9. Non-brand search campaign with three to five ad groups for your highest-revenue categories, phrase and exact match, bidding on maximize clicks with a max CPC at first.
10. Additionally, or instead, once the feed is solid: one Performance Max campaign with one asset group per product area, audience signals from existing customer lists, and brand exclusions.
11. Work through the search terms report twice a week and exclude what does not fit. In the first weeks this single habit has the largest effect.
12. Do not touch bids while a campaign has fewer than 15 conversions.

Days 31 to 60: steer

13. Switch to maximize conversion value once conversions are steady, at first without a target ROAS.
14. Move well-performing queries out of Performance Max reports and into the search campaign as their own keywords.
15. Sharpen assets: replace headlines rated low, add sitelinks and snippets, add image assets.
16. Rework or remove landing pages with many clicks and few orders.
17. Look at auction insights to judge whether you are held back by missing visibility or by a missing conversion rate.
18. Read the recommendations in the account, but apply only what fits your structure. Turn auto-applied recommendations off if you want to keep control.

Days 61 to 90: expand

19. Set a target ROAS derived from your margin, and adjust in small steps.
20. Increase budget where campaigns are limited by budget and still hitting the target.
21. Pull weak product areas into their own campaign with their own target instead of dragging them along in the average.
22. Only now consider Display, Demand Gen or Video, with their own budget and their own expectations.
23. Book a fixed monthly slot for reviewing the account. A recurring rhythm for this and the rest of your numbers is in the weekly routine for growing stores.

New customers, repeat customers, seasonality

A store that only looks at the last 30 days of ROAS judges advertising too harshly, because part of the return arrives as second and third orders. So keep two figures apart.

• Cost of a first order. You can afford more here if you know customers come back. Performance Max has a new customer acquisition setting with three modes: bid higher for new customers, bid higher for high-value new customers, or bid for new customers only. The last one restricts heavily and only fits if you reliably reach existing customers by email and organic channels. All of them need value-based bidding and a purchase goal.
• Cost of an order overall. That is the number for the monthly budget question.

For re-engaging your own customers you need audience lists, from the site tag and from uploaded customer lists. They work twice over: as an audience in Display and Demand Gen, and as a signal in Performance Max.

On seasonality: plan budgets by month, not as one rigid annual figure. Click prices rise in peak periods, so a target ROAS that worked in June can block the budget in November. Loosen targets slightly before the season, watch contribution margin rather than ROAS alone, and raise budgets ahead of the peak rather than in the middle of it.

The mistakes that cost the most at the start

1. Advertising without verified tracking. Everything after that rests on wrong numbers.
2. Too many campaigns with too little budget. None collects enough conversions, so none learns.
3. Mixing brand queries with the rest. The average looks healthy while new customer acquisition stays invisible.
4. Broad match without maintained negatives. The fastest way to lose budget on searches with no buying intent.
5. Judging ads in isolation. If the store converts at 0.5 percent, no account structure will fix that; the work belongs in the ecommerce conversion rate first, on product pages, shipping cost and checkout.

If clicks arrive and orders do not, work through the nine causes of clicks but no conversions in Google Ads in order rather than changing five things at once.

Which numbers you actually watch

Daily, three numbers are enough: cost, conversion value, ROAS. Weekly, add search terms, conversions per campaign, impression share and click-through rate. Monthly: contribution margin after ad spend, new customer share, value by product area.

What you do not use as a steering metric: cost per click on its own, optimization score, or ad strength as an end in itself. All three can improve while your result gets worse.

One note on attribution. Google Ads counts conversions by click date and, depending on your setting, with data-driven or last click attribution. Your store counts orders by order date. The two will never match exactly. Use Google Ads for decisions inside the channel, and contribution margin from your store for the question of whether the channel carries itself at all. In ecomando both sources land on the same daily timeline, so that comparison does not have to be assembled by hand.

The official documentation on campaign types, bidding strategies and reports is in the Google Ads Help Center.