Google Ads Governance Playbook
The operational framework for pacing, capping, and protecting ad spend across SKUs and categories. Built for ecommerce brands spending £10k+ per month on Google Ads.
Budget Pacing Math
Budget pacing prevents the two most common governance failures: overspending early in the month (leaving nothing for high-intent days) and underspending (missing profitable volume).
Core Formula
Daily Budget = Remaining Monthly Budget / Remaining Days
Example: £30,000 monthly budget, day 12 of 30, £14,400 spent so far.
Remaining: £15,600 / 18 days = £866.67/day
Day-of-Week Adjustment
Apply multipliers based on historical conversion rate by day. Typical ecommerce pattern:
Mon
1.15x
Tue
1.20x
Wed
1.10x
Thu
1.05x
Fri
0.95x
Sat
0.80x
Sun
0.75x
Monthly Caps
Monthly caps prevent runaway spend. Google can overspend your daily budget by up to 2x on any given day (and up to 30.4x your daily budget per month). Without hard caps, a high-traffic day can consume disproportionate budget.
Cap Hierarchy
Account Level
Total monthly spend ceiling across all campaigns
e.g. £50,000
Campaign Level
Per-campaign monthly cap based on SKU role
e.g. £8,000 (Profit), £15,000 (Scale)
SKU Group Level
Category or product-group cap within campaigns
e.g. £3,000 per category
Overspend Risk Without Caps
12-18%
Accounts without monthly caps typically overshoot budget by 12-18% due to Google's daily overspend allowance compounding across campaigns.
According to JudeLuxe analysis, February 2026
Negative Keyword Governance
Negative keywords are the most under-managed lever in Google Ads. Without a governance framework, accounts accumulate 15-30% wasted spend on irrelevant queries over 6 months.
Shared Negative Lists
Maintain 4-6 shared negative keyword lists: Brand Terms (for non-brand campaigns), Competitors, Informational Intent ('how to', 'what is', 'free'), Returns/Complaints, and Irrelevant Modifiers.
Weekly Search Term Audit
Review search terms weekly. Flag any query below 1% CTR or with zero conversions over 100 clicks. Add negatives before they compound into wasted spend.
Cross-Campaign Cannibalisation
Use campaign-level negatives to prevent Shopping and Search campaigns from competing on the same query. Route high-intent branded terms to brand campaigns only.
Negative Match Type Hygiene
Use exact match negatives for precision (block 'free' not 'free delivery'). Use phrase match for broader exclusion patterns. Review quarterly for over-blocking.
Wasted Spend from Poor Negatives
15-30%
Accounts without structured negative keyword governance waste 15-30% of budget on irrelevant search terms within 6 months.
According to JudeLuxe analysis, February 2026
Smart Bidding Safeguards
Smart Bidding optimises for Google's objective, not yours. Without safeguards, the algorithm will chase volume at any margin, overbid on branded queries, and exploit your budget on low-intent traffic.
Safeguard Checklist
Margin-Aware Reallocation
Reallocation is the act of moving budget from lower-margin campaigns to higher-margin ones. The trigger is contribution margin per pound of ad spend, not ROAS.
Reallocation Formula
Priority Score = (Contribution Margin per Sale / CPA) × Stock Weeks
SKU groups with the highest priority score get budget first. Stock weeks prevents over-investing in items that will sell out regardless. A score below 1.0 means the campaign is destroying value.
| SKU Group | CM/Sale | CPA | Stock Wks | Score | Action |
|---|---|---|---|---|---|
| Premium Coats | £45 | £18 | 8 | 20.0 | Increase budget |
| Basic Tees | £6 | £12 | 24 | 12.0 | Reduce; clearance |
| Accessories | £22 | £10 | 4 | 8.8 | Hold; low stock |
| Sale Items | £3 | £8 | 16 | 6.0 | Reduce |
Budgeting Calculator
Enter your inputs to calculate daily budget pacing, break-even ROAS, and budget allocation per SKU group.
Automation Scripts
These pseudo-scripts illustrate the logic behind governance automation. Adapt to your Google Ads Scripts environment or use as specifications for your development team.
// Pause low-performing weekend campaigns
// Run: Daily at 00:05
const WEEKEND_PAUSE_LABELS = ["weekend-pause"];
const today = new Date().getDay(); // 0=Sun, 6=Sat
if (today === 0 || today === 6) {
// Pause campaigns labelled for weekend reduction
campaigns.withLabel(WEEKEND_PAUSE_LABELS)
.forEach(campaign => {
campaign.pause();
log("Paused: " + campaign.getName());
});
} else {
// Re-enable on weekdays
campaigns.withLabel(WEEKEND_PAUSE_LABELS)
.forEach(campaign => {
campaign.enable();
log("Enabled: " + campaign.getName());
});
}// Check if PMax campaign POAS drops below floor
// Run: Every 4 hours
const POAS_FLOOR = 1.2; // Minimum acceptable POAS
const BUDGET_CAP_PERCENT = 0.5; // Reduce to 50% of budget
pmaxCampaigns.forEach(campaign => {
const stats = campaign.getStats("LAST_7_DAYS");
const revenue = stats.getConversionValue();
const cost = stats.getCost();
const estimatedProfit = revenue * GROSS_MARGIN;
const poas = estimatedProfit / cost;
if (poas < POAS_FLOOR && cost > 100) {
const currentBudget = campaign.getBudget();
const newBudget = currentBudget * BUDGET_CAP_PERCENT;
campaign.setBudget(newBudget);
alert("POAS breach: " + campaign.getName()
+ " | POAS: " + poas.toFixed(2)
+ " | Budget reduced to £" + newBudget);
}
});// Alert when IS lost to budget spikes above threshold
// Run: Daily at 09:00
const IS_LOST_BUDGET_THRESHOLD = 0.25; // 25%
const ALERT_EMAIL = "[email protected]";
campaigns.forEach(campaign => {
const stats = campaign.getStats("YESTERDAY");
const isLostBudget = stats.getSearchImpressionShareLostBudget();
if (isLostBudget > IS_LOST_BUDGET_THRESHOLD) {
sendEmail(ALERT_EMAIL, {
subject: "IS Lost Alert: " + campaign.getName(),
body: "Impression share lost to budget: "
+ (isLostBudget * 100).toFixed(1) + "%"
+ "\nCampaign: " + campaign.getName()
+ "\nAction: Review budget allocation"
});
}
});Frequently Asked Questions
What is Google Ads budget governance?
Budget governance is the discipline of controlling how ad spend is allocated, paced, and protected across campaigns. It prevents overspend on low-margin SKUs, enforces daily and monthly caps, and ensures reallocation decisions are driven by contribution margin rather than platform ROAS.
How do you calculate daily budget pacing?
Daily budget pacing divides the remaining monthly budget by the remaining days in the month. If you have £15,000 left with 10 days remaining, your daily target is £1,500. Adjust for day-of-week patterns: weekdays may need 15-20% more budget than weekends for B2B-adjacent ecommerce.
When should you pause a Google Ads campaign?
Pause campaigns when the SKU's contribution margin turns negative after ad spend, when stock levels drop below 2 weeks' supply, when the campaign's marginal CPA exceeds the product's gross profit, or when impression share data shows you're competing in an unprofitable auction.
What is margin-aware reallocation in Google Ads?
Margin-aware reallocation shifts budget from low-contribution-margin campaigns to high-margin ones in real time. Rather than spreading budget evenly or chasing ROAS, you calculate the contribution margin per pound of ad spend for each SKU group and reallocate to maximise total profit.
How do Smart Bidding safeguards work?
Smart Bidding safeguards include setting maximum CPC bid limits, applying portfolio bid strategies with shared budgets, using seasonal adjustments for predictable demand changes, and monitoring auction-time signals. These prevent the algorithm from overbidding during low-intent periods or chasing volume at the expense of profit.
What impression share level should I target?
There is no universal target. High-margin, low-competition SKUs should aim for 80%+ impression share. Competitive, lower-margin categories may be profitable at 40-60%. The key metric is marginal cost per impression share point: if gaining the next 5% of IS costs more than the profit it generates, stop.