Choosing the right Google Ads agency can make or break your digital marketing success. The right partner will help you lower costs, boost conversions, and scale your campaigns with data-driven precision, while the wrong one can drain your budget with little to show for it. Whether you’re new to paid search or looking to switch agencies, knowing what to look for is essential.
This guide walks you through a clear evaluation process, including a free downloadable checklist and the key KPIs every smart advertiser should track.
🔷 Why Evaluating a Google Ads Agency Matters
Choosing the wrong Google Ads agency can cost more than just wasted ad spend — it can stall your growth, damage your brand, and leave you playing catch-up in a competitive market. Common pitfalls include agencies that overpromise but underdeliver, lack transparency, or rely on outdated tactics instead of data-driven strategies.
For example: an inexperienced agency might prioritize traffic volume over conversion quality, leaving you with lots of clicks but few sales.
In contrast, the right agency acts as a growth partner: fine-tuning campaigns, optimizing every pound spent, and constantly adjusting strategy to improve ROAS and unlock long-term business growth. Careful evaluation helps you avoid missteps and ensures you partner with experts who can deliver measurable success.
🔷 Agency Evaluation Checklist
🔷 KPIs Your Agency Must Track & Report
A results-driven Google Ads agency won’t just focus on clicks — they’ll monitor the metrics that actually move the needle for your business. Here are 7 essential KPIs every competent agency should track and report on regularly:
- Click-through Rate (CTR)- A strong CTR shows your ads are relevant and engaging. Low CTR often signals poor targeting or weak creative, both of which need immediate attention.
Example: If your ad shows 1,000 times but only gets 10 clicks, that’s a 1% CTR. Higher CTR means your ads are relevant and compelling. - Cost-per-Acquisition (CPA)- This measures how much you’re paying for each conversion (lead, sale, or action). Lowering CPA while maintaining or improving lead quality is a key sign of optimization.
Example: If you spend £500 and get 10 new customers, your CPA is £50. Great agencies work to lower this while keeping lead quality high.
- Conversion Rate- It’s not enough to get clicks — your landing pages must convert visitors into customers. A skilled agency will continually refine ad copy, targeting, and on-site experience to improve this rate.
- Impression Share- This reveals what percentage of the total available ad impressions your ads are capturing. A low impression share could indicate limited budget or high competition.
Example: If your ads only show 40% of the time they’re eligible, you’re losing visibility to competitors. Agencies track this to maximize your reach. - 5. Quality Score- Google assigns this score based on ad relevance, expected CTR, and landing page experience. Higher scores lower your costs and improve ad placement.
Example: Google rates your ads from 1-10. A score of 8+ often leads to lower costs and better ad placements.
- 6. ROAS (Return on Ad Spend)- This is the ultimate performance metric for any campaign. A great agency aims for a healthy and scalable ROAS, not just short-term wins.
Example: If you spend £1,000 and generate £5,000 in revenue, your ROAS is 5:1. Agencies should focus on scaling this ratio sustainably. - 7. Lifetime Value (LTV) vs. CPA- A savvy agency will go beyond single transactions and look at the long-term value of a customer compared to acquisition costs — helping ensure campaigns are truly profitable over time.
Example: If a customer’s LTV is £1,000 and your CPA is £200, you’re in profit. Agencies should aim for this healthy gap, not just short-term sales.
🔷 Red Flags To Watch Out For
Even the best sales pitch can hide a poor agency relationship. Watch for these warning signs before signing any contract:
- Overpromising results- If an agency guarantees instant success or “#1 rankings” overnight, it’s usually too good to be true. Google Ads success takes testing and optimization, not shortcuts.
- Lack of transparency in reporting- You should always know where your budget is going. Vague or infrequent reports are a major red flag.
- No regular strategy meetings- If an agency isn’t proactively reviewing performance and refining your campaigns with you, they’re not invested in long-term success.
- One-size-fits-all approach- Every business is unique. If the agency doesn’t customize its strategy for your industry, audience, or goals — expect poor results.
- Vague contract terms- A reliable agency offers clear deliverables, timelines, and exit terms. If the contract feels fuzzy, so will the service.
🔷 Questions To Ask Before Your First Meeting
The first meeting with a Google Ads agency is your chance to dig deeper into their expertise, approach, and alignment with your goals. Here are some important questions to ask:
- Can I see case studies relevant to my industry?
Ask the agency for specific examples of campaigns they’ve managed in your industry. Look for case studies that demonstrate tangible results, such as increased conversions or improved ROAS. If they can’t provide relevant examples, it might signal a lack of experience in your niche.
- How do you determine budget splits?
Understanding how the agency allocates your budget is crucial. Inquire about how they decide the split between Google Search, Display, Shopping, and other networks. The right agency will make data-driven decisions based on your goals, audience, and the performance of different channels.
- What happens if performance stagnates?
Campaigns don’t always perform perfectly right away. Ask the agency about their strategy for handling stagnation. A good agency will have a clear process for testing, adjusting, and optimizing underperforming campaigns to ensure your budget is spent efficiently and results improve over time.
- Who will be managing my account?
It’s essential to know who will be directly handling your account. Ask about the experience and qualifications of the team members who will be working on your campaigns. Ideally, the account manager should have a deep understanding of your industry and a proven track record in managing Google Ads campaigns for similar businesses.
Actionable Takeaway: Choosing the right Google Ads agency is a significant decision that should be based on data, not just promises. Always ensure that the agency prioritizes performance metrics, with clear KPIs like ROAS, CPA, and conversion rates at the forefront of their strategy. A data-driven approach helps ensure transparency and accountability, so you know exactly where your ad spend is going and what it’s generating in return.
Before making the switch to a new agency, consider auditing your current campaign performance. This will give you a baseline to measure improvements and ensure the new agency is delivering on their promises.
Have doubts? Schedule a free PPC audit with our senior strategist to evaluate your current campaigns and receive tailored recommendations for optimizing your Google Ads performance.
