Spot the Difference: "Could You" vs "Would You"

Basically every day, at least one student will ask a question like, “Tutor, what’s the difference between X and Y?”

Sometimes, the difference is easy to explain. Other times, though, these questions remind me of those “spot the difference” puzzles – the challenging kinds where the differences are as hard to find as a needle in a haystack. 

And it doesn’t help that some students aren’t satisfied until they get some definitive-sounding but overly simplified answer like “X is more polite than Y.”

So to give tutors a hand, we’ll try to tackle questions like these in our posts. And we’ll start with “What’s the difference between ‘Could you’ and ‘Would you’ requests?” as in:

• Would you please close the door?
• Could you please close the door?

Is one of these correct and the other not? Or is one of these more polite than the other? Read on to find out.

The Issue

A large part of the confusion comes from the fact that textbooks, courses, and native speakers all seem to disagree on this issue. For example, here are three explanations we found online:

1. “Would you” is correct, because you are asking if someone will do something and not whether they can do it. “Would you” also sounds more polite than “Could you.” 
2. “Would you” and “Could you” are equally polite and valid ways to make a request. 
3. “Could you” sounds more polite than “Would you.” “Would you” sounds more insistent and is more often used in angry requests, such as “Would you please hurry up!”

So how are English learners supposed to know which one to use? 

What the Data Says

To get to the bottom of this mystery, we first consulted some large libraries of spoken and written English. Here’s what they had to say.

In formal situations:

• “Would you” and “Could you” are both used. For example, searching through US Supreme Court cases, we found that judges made requests with both “Would you” and “Could you.”
• “Would you” is more common. For example, people delivering speeches ask people to stand up using both, but the “would” version is about seven times more common in subtitled speeches on YouTube: close to 300 results for “Would you” but just 39 for “Could you.”

And in informal situations:

• Both “Would you” and “Could you” are also used. 
• In some instances, they appear with equal frequency. For example, the set phrase “Would/Could you do me a favor?” appeared almost an equal number of times in either form in libraries of modern American English and English used globally online. The number of times both “Could you” and “Would you” were used to make angry or impatient requests (e.g. “Would/Could you please just … ”) were also roughly equal.
• However, in other instances, “Could you” is more common. For example, “Could you lend me … ?” and “Could you get me … ?” were two to three times as common as their “would” counterparts.

So it seems that “Would you” and “Could you” are often interchangeable. However, “Would you” is more common in formal English and “Could you” is more common in casual, everyday situations.

How to Explain This to Students

At this point, some students might think, “So ‘Would you’ is more polite, right? I’ll just default to that then.” And there’s nothing wrong with this.

But if your student actually cares about sounding polite, fixating on the difference between “would” and “could” isn’t the right way to go about that.

For starters, the data doesn’t say that “Would you” is more polite. It simply says that it’s more common in formal situations. And politeness and formality are two different things.

Politeness ultimately depends on how a listener interprets what a speaker says, and given the data, it seems most people wouldn’t notice which word was chosen, let alone interpret it as rude.

What people will notice is the tone of voice. For example, experts at Merriam Webster and the Chicago Manual of Style say that the difference between “Could you” and “Would you” is trumped by matters of tone and context. They provide the following example sentences:

1. “Would you do me a favor?”
2. “Would you please just shut up.”

1. “Could you please email me the directions to your house?”
2. “Could you PLEASE turn off the lights in your room?” 

In either set, the first sentence is polite while the second isn’t, and this has nothing to do with whether “would” or “could” was used.

So if a student actually cares about politeness, we can encourage them to focus on more important things like their tone of voice – and to stop worrying about the intricacies of “would” and “could.”

👋 That’s It For Now!

We hope this post gives tutors an idea of how “could” and “would” differ as well as an understanding of how to handle questions regarding their differences.

When asked questions like this, keep in mind that:

1. Some students are not ready to productively explore the differences between two words.
2. Sometimes, the things students most want to know don’t actually help them achieve their goals (in this case, sounding polite).

If you find this blog post helpful, make sure to let TS know, and we’ll make more of these! You can also let us know other questions students often ask you and we’ll try our best to answer them.