How Long Should a Sermon Be? What the Data Actually Says

Someone has said it to you. Maybe kindly, maybe over coffee, maybe in the parking lot with a hand on your shoulder: the sermon's been running a little long lately. And whatever you said back in the moment, what you actually did was go home and start counting minutes.

So how long should a sermon be? There's more real data on this than most pastors realize. Let's put it on the table first—and then talk about what the number is actually measuring, because it isn't what you think.

The average sermon length, by the numbers

In 2019 the Pew Research Center did something nobody had done before: they scraped and transcribed 49,719 sermons that 6,431 US churches had posted online over about eight weeks, and measured them. The study is called "The Digital Pulpit," and it's still the largest honest look we have at how long American preachers actually preach.

The median sermon ran 37 minutes.

But the median buries the interesting part. Sermon length by denomination splits almost four to one:

• Catholic homilies—a median of 14 minutes
• Mainline Protestant—25 minutes
• Evangelical Protestant—39 minutes
• Historically Black Protestant—54 minutes

One detail in that data is worth pausing on. Historically Black Protestant sermons are roughly as long as evangelical sermons by word count, but 38% longer by the clock. The extra time isn't more content. It's musical interludes, call and response, the dramatic pause that lets a line land. In that tradition, length isn't padding—it's form. Which is the first crack in the idea that there's one right number.

What your congregation actually prefers

Pew tells you what preachers do. Lifeway Research asked what people in the pews want, surveying about a thousand Protestant pastors and a thousand churchgoers in the fall of 2019.

Churchgoer preference clusters in the middle: 27% like 20 to under 30 minutes, 25% like 30 to under 40. So a slim majority wants somewhere in the 20-to-40 window. But 12% want an hour or more, which should keep anyone from turning "shorter" into a law.

Then the number that stings a little: 27% of churchgoers say their pastor preaches longer than they'd prefer. Thirteen percent say shorter. Fifty-five percent say it's about right.

And one more, which I think is the most useful finding in the whole survey. Eighty-five percent of pastors said their sermons run under 40 minutes. Only 66% of their congregants estimated the same thing.

Nobody's lying. It's that a meandering sermon feels longer than it is. Perceived length and clock length are two different measurements, and your people are grading you on the first one.

The attention research, honestly

You've heard the line: people can only pay attention for ten or fifteen minutes, so keep it short. You may have also heard that humans now have shorter attention spans than goldfish. Cut that second one out of your vocabulary—it traces back to no real study at all.

The first one deserves better treatment, because it's not quite a myth so much as a claim that was never earned. Bradbury's 2016 review in Advances in Physiology Education went looking for the primary research behind the 10-to-15-minute attention limit and found that the source everyone cites barely discusses attention at all. The available data don't support a fixed limit. Attention rises and falls throughout a lecture with no reliable downhill slide at minute twelve.

Here's the finding that should actually change how you prepare: the greatest variability in listener attention came not from the format or the length, but from differences between the teachers.

Attention isn't a fuel tank that empties on a schedule. It's a running verdict on whether the next sentence is worth hearing.

Length is a symptom, not a virtue

Which brings us to the thing the data can't tell you.

There's a respected shorter-is-better school in preaching, and it isn't wrong. Tim Keller put it plainly: "In general I think for most Sunday congregations the sermon should be under 30 minutes. That's safest." Notice the word he chose. Safest. That's advice about risk, not about truth. Mark Dever gets closer to the real principle: "A sermon should be as long as a preacher can well preach and a congregation can well listen."

Still a range, though. Not a rule. Here's the rule I'd offer instead, and it's the one thing in this article I'd defend hardest:

Sermon length is downstream of clarity.

If you can say the one thing this sermon is saying in a single sentence—before you write a word—the sermon shortens itself. Every illustration either serves that sentence or it doesn't, and cutting becomes easy because the test is obvious.

If you can't say it in one sentence, you preach longer to compensate. Not on purpose. You circle. You give three partial answers hoping one of them lands. You add a fourth point because the first three didn't close. You stack illustrations because none of them is quite the illustration. That extra fifteen minutes is usually not extra content at all—it's the search for the big idea, conducted live, in front of your people, on Sunday morning.

A sermon that runs long is rarely a length problem. It's a clarity problem that found somewhere to hide.

Which also explains why "just preach shorter" so often fails. Cut a foggy 45-minute sermon to 30 and you get a foggy 30-minute sermon, minus the parts where you were groping toward the point. The fix isn't the timer. It's the clarity stage of your prep week—the stage that doesn't reward more hours, only better attention.

What to actually do this week

Not "cut to thirty minutes." Try this order instead:

1. Write the big idea as one sentence before you draft. If it takes you two sentences, you're not ready to write yet. That's not a delay—that's the work. Here's the weekly rhythm we use.
2. Play back last Sunday and mark the minute the idea arrived. If it shows up at minute 22 of a 45-minute sermon, the first 21 minutes were prep you did out loud.
3. Ask what every section is for. Anything that doesn't advance, prove, or apply that one sentence comes out—no matter how good it is. Especially if it's good. Good material is the hardest to cut and the most common reason sermons bloat.
4. Then set the clock to fit your people. Your tradition already has a range. If you're well above your tradition's median and your elders keep mentioning it, that's two independent signals, and two is enough.

I should say plainly where I sit: we build an AI sermon coach, so I have an interest here. The relevant part is what it actually does—it won't move forward until you can state your big idea in one sentence. Not because brevity is holy. Because vagueness is the thing that inflates a sermon, and vagueness is very hard to see from the inside on a Thursday night.

One step: pull up your notes for this Sunday and write your big idea at the top in one sentence. If it comes easily, preach as long as the text and your people can carry. If it doesn't, don't touch the timer yet—you've found the actual problem, and it's a better one to solve.