Please Approve By Friday Does Nothing. Here Is What Makes A Client Say Yes: Agency Client Approval Process

Your agency client approval process has a step you cannot see. This piece is about that step.

Six trials tested the deadline. It changed nothing

Scientists have run 481 tests on one question. How do you get a busy stranger to send something back?

Six of those tests tried a deadline. "Please reply by this date."

The deadline changed nothing. Not a little. Nothing.

Now look at your Tuesday.

You have eight posts drafted for five clients. Six of them are waiting for a yes.

Each one went out with the same line. "Please approve by Friday."

Friday comes. You send a reminder. On Monday you phone. The yes arrives the next Wednesday.

By then the day the post was written for has passed.

One survey asked 500 people who work in marketing. More than 60 in 100 said they lose up to a full day a week chasing approvals. And 85 in 100 said approvals run past the planned date (StreamWork, survey by Pollfish, October 2025). StreamWork sells approval software, so read it with that in mind.

Your clients feel the wait too. In a 2026 survey of 494 agency people, 44 in 100 said clients want their work back faster (AgencyAnalytics, 2026).

So if the deadline does nothing, what does make a client reply?

What you will know by the end

Most advice on this says chase harder, or buy a tool. Both leave out what the tests actually found.

By the end of this piece you will know:

• Which reminders work, and in what order. One you use every day does not.
• Why the famous study about deadlines fell over last year.
• What the wait looks like from your client's chair. It is not what you think.
• One rule that ends the chase, and where the number in it should come from.

Let us start with a permission slip.

The school slip that never came back

A teacher sends a slip home. "Please sign and return by Friday." Half the class never brings it back.

Every parent meant to. The slip went into a school bag and stayed there.

Your approval email is that slip. So it helps to know what actually gets a slip back.

A group of researchers collected every fair test they could find on this. The question was simple. What makes a busy person send a form back? They found 481 tests by post, trying 110 different methods (Edwards and others, Cochrane review, 2009).

They measured each method as odds. Odds of 1.00 means no change. Odds of 1.50 means the form came back about half again as often.

Here is what worked, strongest first.

• A shorter form. Odds 1.64. The biggest thing the sender controls.
• Sending the form again with the reminder, not just a note. Odds 1.46. Eleven tests, 8,619 people.
• Any reminder at all. Odds 1.35. Nineteen tests, 32,778 people.
• A hand signed, personal touch. Odds 1.14. Small but real, across 58 tests.

And one that did not work. Phoning people instead of posting the reminder. Odds 0.86. No better, and maybe worse.

Think about what most agencies do first when a post is stuck. They phone.

So a shorter ask and a second send help. What about the deadline?

Why the Friday in your email does almost nothing

The same review looked at deadlines. Six tests, 5,661 people. Some forms said "please reply by this date." Some did not.

The result was odds of 1.00. No effect at all (Edwards and others, 2009).

By email it was a little better. One large test of 8,586 people found a deadline raised the odds to 1.18. A small lift, not a big one.

You may have read that deadlines make people do the work. That idea comes mostly from one famous study.

In 2002, two researchers gave students some texts and asked them to find the spelling mistakes. Some had fixed deadlines. Some set their own. Some had none. The fixed deadlines seemed to work best (Ariely and Wertenbroch, Psychological Science, 2002). Other researchers have pointed to that paper more than 2,000 times.

In September 2025 two other researchers ran the same study again. They wrote their plan down before they started. Their result: "the results of the paper do not replicate." Changing the deadlines had "a negligible effect" (Hyndman and Bisin, 15 September 2025). In plain words, the deadlines made almost no difference.

One honest note. These tests were about forms sent to strangers, not posts sent to clients. The pattern carries over. The exact numbers do not. That is our reading, not theirs.

But that is only half of it. The other half sits on your client's desk.

What the wait looks like from the client's chair

Every year a research firm interviews the clients of creative agencies. In 2026 they spoke to 700 of them (What Clients Think 2026, Up to the Light with the DBA, April 2026).

One thing clients said they wish agencies knew: how sign off works inside their company. Sign off means who has to say yes before a post can go out.

The report puts it plainly. A "quick request for approval" can annoy someone if the process takes a week in reality.

So your client is not ignoring you. Your post is sitting in a queue you cannot see. Your reminder lands on someone who cannot move it faster.

Here is the part nobody expects. 64 in 100 of those clients said their agency could be "more assertive" or tougher with them.

The report's author is Jonathan Kirk. He says the agency's job is "taking the pressure off clients", and showing it is in full control.

In plain words: clients want you to decide what happens when they go quiet.

There is a name for that. A rule for silence.

Drew McLellan, who trains agency owners at the Agency Management Institute, shares a contract clause for it. The client agrees to give feedback within three business days. If no reply comes, the work counts as approved and the agency goes ahead (Agency Management Institute). This is not legal advice. Ask a lawyer before you put it in a contract.

Why would a rule like that work, when a deadline did not?

Go back to the school slip. "Return by Friday" is a request. "No slip, no trip" is a rule about what happens if you do nothing. The second one gets every slip back.

Researchers call this a default. In 2019 a team put together 58 studies of defaults, 73,675 people in all. Defaults had a large effect on what people did (Jachimowicz and others, Behavioural Public Policy, 2019). They worked best when people saw them as the normal way things are done.

The same review found the limit. Several studies showed no effect. Two showed the opposite. A rule that feels like a trick gets treated like a trick.

And one more limit. A three day rule fights a client whose sign off takes a week. The number in the rule has to match their real process.

That gives you five things to change.

Five things to change this week

1. Cut the approval request to one screen. The post, one line saying what it is for, one plain yes. Nothing else. The shorter form was the biggest lift in the tests.
2. On the second send, attach the post again. Never send "any update?" on its own. Sending the thing again beat sending a note about it.
3. Ask each client one question. "How many days does sign off really take on your side?" Write the answer down.
4. Write the rule with that number. "If we hear nothing after X working days, we send one last reminder with the post. If it is still quiet, it goes out as written."
5. Say the rule out loud at the start of the work. Never hide it in the contract. A rule the client agreed to feels normal. A rule they discover later feels like a trick.

Here is the whole lesson in two lines. A deadline asks the client to do something. A rule for silence decides what happens when they do nothing.

What this evidence cannot tell you

• The 481 tests were about forms sent to strangers. Nobody has run the same tests on client approvals.
• StreamWork sells approval software. AgencyAnalytics sells reporting software. Both surveys are their own.
• The 700 clients were clients of UK design and creative agencies. Your clients may differ.
• No study has tested a silence rule in an agency contract. The rule rests on the defaults research and on practice.
• Approval is not quality. In the StreamWork survey, 58 in 100 said approved content still goes live with errors. A silence rule ends the wait. It does not check the post.
• Clients in banking, health or medicine often must review by law. Do not use a silence rule there.
• None of this is legal advice.

Frequently asked questions about the agency client approval process

Is a silence rule legal?

Clauses like it are common in contracts. Whether it holds depends on your country and how it is written. Ask a lawyer.

How many days should the rule give?

Ask the client how long their sign off really takes. Use that number. A rule the client cannot meet is a rule they will break.

What if the client says no to the rule?

Then you have learned something early. Ask what they would agree to instead. Even a five day rule beats no rule.

Does this work with a brand new client?

It works best there. Agree the rule before the first post. Changing the rules on an old client is harder.

Should I still phone?

The tests found phoning did not help. Send the post again instead. Phone only when the client asks you to.

One question for you

How many days does your slowest client take to say yes to one post?

And have you ever told them that number?