A brand new study just dropped. And it says something most people in marketing don't want to hear.

Forrester and the 4As released their State of AI Inside US Marketing Agencies report at Cannes Lions 2026. They found that nine out of ten agencies now use AI. Sounds great, right?

Not so fast.

The study found that most agencies are using AI to cut costs. Not to do better work. They are trading creativity for speed. And that is bad news for every business that hires an agency to grow.

What the Study Found

Here are the numbers. Ninety percent of US marketing agencies now use generative AI. Half of them use agentic AI. That means AI tools that do tasks on their own. No human clicks needed.

But look at why they use it. Eighty one percent said the main goal is to boost staff productivity. Sixty three percent said the same for AI agents. The top use cases are building creative content, writing SEO strategy, and speeding up internal work.

In other words, most agencies are using AI to do the same work faster and cheaper. But they are not using it to do better work.

Why This Matters for Your Business

If you hire a marketing agency, this study should make you ask some tough questions. Because here is the thing. When an agency uses AI just to cut corners, your business pays the price.

You get generic blog posts that sound like every other website in your industry. You get ad copy that hits all the right keywords but says nothing real. You get social media posts that look polished but don't connect with anyone.

And the worst part? You might not notice right away. The work looks fine on the surface. But six months later, your leads are flat. Your brand sounds like a robot. Your customers can't tell you apart from the guy down the street.

The Two Types of AI Agencies

This study makes something clear. There are now two types of marketing agencies in the world:

• Cost-cutters - They use AI to do your work faster so they can take on more clients. You pay the same but get less attention and less creativity.
• Quality builders - They use AI to do deeper research, test more ideas, and deliver work that actually moves the needle. AI makes their team smarter, not just faster.

The difference is not whether an agency uses AI. Everyone does now. The difference is how they use it.

How to Tell If Your Agency Is Using AI the Right Way

Here are five questions to ask your marketing agency today:

1. Is my content unique to my business? If your blog posts could work for any company in your field, AI is doing the writing. Nobody is adding your voice or your stories.

2. Are you testing new ideas or just repeating what worked before? Good agencies use AI to test new angles and find what clicks. Lazy ones use it to pump out more of the same.

3. Can you show me data behind your decisions? AI gives teams better data than ever. If your agency is still guessing, they are using AI for the wrong things.

4. How many clients does each team member manage? If that number keeps going up, the agency is using AI to stretch thin. Not to serve you better.

5. Is my brand voice consistent? If everything sounds the same across all your channels - and sounds like everyone else too - that is a red flag.

What Smart Agencies Do Differently

At SpeedMobi , we work with over five thousand local service businesses. We use AI every day. But we use it to make our work better, not just faster.

Here is what that looks like:

• Deeper research. AI helps us scan hundreds of data points to find the real chances for your business. Not just the obvious ones.
• Better targeting. We use AI to study your market, your rivals, and your customers. Then we build campaigns that speak to your specific audience.
• Smarter testing. AI lets us test more versions of ads, landing pages, and content. We find what works faster so you get results sooner.
• Human creativity on top. AI handles the data. Our team handles the thinking. Every piece of content gets a human brain and a real strategy behind it.

What This Means Going Forward

The Forrester study said something else that matters. Agencies that only cut costs with AI are hurting brand growth. The damage adds up over time.

If your agency cuts corners today, your brand will be weaker six months from now. Your rivals who invest in real ideas will pull ahead. And catching up gets harder every month.

The smart move is to make sure your marketing partner uses AI to boost ideas. Not replace them.

The Bottom Line

AI is not the problem. The problem is how most agencies use it. Nine out of ten agencies use AI. But most of them are using it to cut costs instead of doing better work for you.

Don't settle for that. Your business is worth more than cookie cutter content. AI should make that easier, not make it generic.

Ask your agency the hard questions. And if you don't like the answers, it might be time for a change.