The InsideSales lead response time study: what the 5-minute research actually found
The InsideSales lead response time study, run with Professor James Oldroyd of MIT on three years of data from six companies, more than 15,000 web leads and over 100,000 call attempts, found that the odds of qualifying a lead fall 21 times when the first response slips from 5 minutes to 30, and the odds of making contact at all fall 100 times. It is the source of the "5-minute rule." It is also the most misquoted study in sales, so below is what it measured, what it found in its own words, how it differs from the Harvard Business Review audit it is confused with, and what it never claimed.
The short version
- Who and what: InsideSales.com with Professor Oldroyd of MIT; three years of call data from six companies; 15,000+ web-form leads; 100,000+ dial attempts. The question: when should a company first call a web lead?
- The 5-minute findings: qualifying odds fall fourfold from 5 to 10 minutes and 21-fold from 5 to 30 minutes; contact odds show a 100-fold difference; across the first hour, contact success drops more than tenfold and qualification more than sixfold.
- Timing: calls from 4 to 6 pm reached leads 114% more often than the worst hour; 8 to 9 am and 4 to 5 pm qualified 164% more often than 1 to 2 pm; Wednesday and Thursday beat every other day. After 20 hours, more dials hurt.
- Not the same study: the Harvard Business Review "Short Life of Online Sales Leads" piece (2011) is a separate audit of 2,241 companies by Oldroyd and colleagues. The 391% figure people attach to both belongs to a third study, by Velocify.
What is the InsideSales lead response management study?
It is a behavioral study of when sales reps should first call a web-generated lead, published as the Lead Response Management Study. In the study's own description, it was done "collaborating with Professor Oldroyd from MIT" and used InsideSales.com's own dataset, "which integrates quantitative call data with qualitative lead process insights." The team "scrutinized three years of data from six diverse companies, analyzing over fifteen thousand leads and more than a hundred thousand call attempts."
The research question is stated in one line: "When should companies initiate contact with web-generated leads for the best contact and qualification outcomes?" That framing matters. The study is about the timing of the first phone call to someone who filled in a web form, and about two outcomes, contact and qualification. It is not a study of conversion rates, closed deals or revenue, although it is quoted that way constantly.
| Term in the study | Definition, in the study's words |
|---|---|
| Lead created time | "The exact moment a potential customer completes and submits a web form." |
| First dial attempt time | "When a sales or lead qualification representative first tries to reach the lead." |
| Contact | "A successful call that results in a conversation of a predetermined duration." |
| Qualify | "The stage where a lead shows willingness to enter the sales funnel," often "marked by scheduling a meeting with a sales representative." |
So "qualified" in this study means the lead agreed to a real sales conversation, usually a booked meeting. When you read "21 times more likely to qualify," read "21 times more likely to agree to a meeting." That is the number a small business should care about, because a booked appointment is the thing an answered call is for.
What did the study find about responding within 5 minutes?
The response-time findings "overshadowed both the day of the week and the time of day in significance," according to the study. The team looked at the first three hours after a lead arrived in 5-minute segments. Every figure below is quoted from the study page.
| Response window | Contact (reaching the lead) | Qualification (lead agrees to a meeting) | Study wording |
|---|---|---|---|
| 5 minutes to 10 minutes | Not stated as a separate figure | Odds fall fourfold | "the chances of qualification dropped fourfold between 5 and 10 minutes" |
| 5 minutes to 30 minutes | 100-fold difference | 21-fold decrease | "a staggering 21-fold decrease in the odds of qualifying a prospect if the response time stretched from 5 to 30 minutes"; "a 100-fold increase in contact ratios and a 21-fold increase in qualification" |
| Within the first hour | Drops more than tenfold | Falls over sixfold | "Contact success dropped more than tenfold, while qualification success fell over sixfold in the first hour" |
| After 20 hours | More dial attempts reduce the chance of contact | "attempts to contact leads after 20 hours could be detrimental, potentially reducing the chances of successful engagement" | |
Two things people get wrong. First, the 100x figure is about contact, the chance of getting the lead on the phone at all; the 21x figure is about qualification. They are different outcomes with different baselines, which is why quoting "100 times more likely to convert" is wrong on both counts. Second, these are changes in odds inside one dataset, not conversion rates you can copy into a forecast. Our speed to lead chart draws the qualification figures on one axis, indexed to a reply at 5 minutes.
What did it find about the best time and day to call?
Less important than speed, by the study's own ranking, but useful for the second and third attempts. The study "intentionally excluded the early morning (7-8 AM) and post-6 PM times as they fall outside typical business hours," so it says nothing about evenings, which is exactly when many small-business leads arrive.
| Finding | Figure | Compared with |
|---|---|---|
| Best hours to make contact | 4 to 6 pm, 114% more effective | 11 am to 12 pm, the least effective hour |
| Best hours to qualify | 8 to 9 am and 4 to 5 pm, 164% more effective | 1 to 2 pm, "the post-lunch period" |
| Best single hour for both | 4 to 5 pm, 109% higher qualification success | 11 am to 12 pm |
| Best days to make contact | Wednesday and Thursday; Thursday 49.7% better | Tuesday, the least effective day |
| Best days to qualify | Wednesday, 24.9% better; Thursday, 19.1% better | Friday, the least effective day |
| Worst day overall | "Monday was consistently ineffective across all categories" | |
Read this table the way the study intends: the first call goes out within minutes whatever the clock says, and the timing data decides when to place the follow-up calls. Waiting for 4 pm to make a first call would trade a 114% gain for a 21-fold loss.
Is the InsideSales study the same as the Harvard Business Review study?
No, and the confusion is the reason half the "MIT/Harvard 5-minute study" citations online point to the wrong paper. There are three separate pieces of research, and one figure that belongs to none of the first two.
| Research | Who | What it measured | Headline figures |
|---|---|---|---|
| Lead Response Management Study (the InsideSales study) | InsideSales.com with Professor James Oldroyd of MIT | Six companies' own call logs: 15,000+ web leads, 100,000+ dials; timing of first call against contact and qualification | Qualifying odds fall 4x by 10 minutes and 21x by 30 minutes; contact 100x; best hours and days |
| "The Short Life of Online Sales Leads," Harvard Business Review, March 2011 | Oldroyd, McElheran and Elkington | An audit: a test lead submitted to 2,241 US companies, timing each reply; plus a separate dataset of 1.25 million leads at 29 B2C and 13 B2B companies | 37% replied within an hour, 16% in 1 to 24 hours, 24% took more than a day, 23% never replied; 42-hour average among those replying within 30 days; leads contacted within an hour "nearly seven times as likely" to qualify |
| "The Ultimate Contact Strategy," Velocify | Velocify | Nearly 3.5 million leads across 400+ companies; call attempts and timing | A first call within one minute raised conversion by nearly 400% (391%); 93% of converted leads were reached by the sixth call attempt |
So: the 21x and 100x figures are InsideSales. The 42 hours, 37% and 23% figures are Harvard Business Review. The 391% and "six calls" figures are Velocify. "MIT" is Professor Oldroyd's affiliation in the InsideSales study; "Harvard" is the magazine that published the later audit. Neither study was conducted by a university. If a slide says "Harvard study: 21x," it has crossed two studies. The speed to lead guide lays out all three with the exact wording and where each was read.
What does the InsideSales study not say?
Enough that a careful reader should treat the direction as settled and the exact multipliers as one dataset's result. The limits, from the study's own description of its method:
- Six companies. The data came from six firms using InsideSales.com's dialer. Their industries are not itemized on the study page, beyond follow-up tests in mortgage and insurance. Your market may decay faster or slower.
- Phone calls only. Every outcome is a dial, a conversation or a booked meeting. Nothing in the data measures a text message or an email reply, because the dataset is call logs.
- Web-form leads only. The study covers "leads obtained through web forms and contacted at least once." Inbound phone calls, walk-ins and referrals are outside it.
- Business hours only. Early morning and after 6 pm were excluded by design, so the study is silent on the evening and weekend leads that answering services and AI receptionists exist for.
- Odds, not rates. "21-fold" is a change in the odds of qualifying within one dataset. It is not "21% more revenue," and it is not a conversion rate you can multiply your lead count by.
- Age. The study page does not state its publication year; the site's copyright line reads 2022. Treat the multipliers as dated and the direction as confirmed by every later study we have read, including the Harvard Business Review audit and the Velocify data.
One more caution on the source itself. The study page at leadresponsemanagement.org is the only place we have found the full findings, and the study text on it is intact, but the foot of the page now carries unrelated injected links. We quote from the study sections only and link with that caveat.
How should a small business apply the 5-minute finding?
By making the first response automatic and the human follow-up scheduled. The study's two numbers, 5 minutes and 20 hours, give you a window: reply inside the first and stop dialing after the second. For a business without a sales floor, that looks like this.
The scripts for steps 2 and 4 are in our lead follow-up call script post, and the four ways to measure your own response time are in the speed to lead guide. The seven fixes, in order, are in how to improve lead response time. If nobody is free to answer inside five minutes, an AI receptionist we build and run does step 1 through 4; first 30 days free, then $297 a month flat, no setup fee; see pricing.
Want to know your own numbers before you change anything? On a free 30-minute Where AI Fits call we pull your real first-response times by hour and by lead source and put them next to the study's windows. If you are already inside five minutes around the clock, we will tell you so and you can keep your money.
Book a Where AI Fits callQuestions about the InsideSales study
Who ran the InsideSales lead response time study?+
What is the 21 times lead response statistic?+
What is the 100 times figure from the study?+
Is the 5-minute study from MIT or Harvard?+
Is the InsideSales study still valid in 2026?+
Where can I read the original InsideSales study?+
- Lead Response Management Study (InsideSales.com with Professor James Oldroyd of MIT). All quotations and figures on this page were read on the study page on September 23, 2026: definitions; three years, six companies, 15,000+ leads, 100,000+ call attempts; fourfold and 21-fold qualification decreases; 100-fold contact ratio; tenfold and sixfold decreases in the first hour; 20-hour finding; best hours and days; excluded hours; mortgage and insurance follow-up tests. leadresponsemanagement.org. The foot of that page carries unrelated injected links; the study text is intact.
- Oldroyd, McElheran, Elkington. "The Short Life of Online Sales Leads." Harvard Business Review, March 2011. 2,241 US companies audited: 37% within an hour, 16% in 1 to 24 hours, 24% over 24 hours, 23% never; 42-hour average among companies responding within 30 days; separate 1.25 million-lead dataset, 29 B2C and 13 B2B companies, nearly seven times as likely to qualify within an hour. Figures read in the article text. hbr.org; record at BYU ScholarsArchive
- Velocify. "The Ultimate Contact Strategy." About 3.5 million leads across 400+ companies; a first call within one minute raised conversion by nearly 400% (391%); 93% of converted leads reached by the sixth call attempt. slideshare.net/Velocify; also quoted in our speed to lead guide.
Published September 23, 2026. Every figure was read on its source and checked again before publishing; see how we research and write. Found an error? Email hello@leadsixty.com.
The study says five minutes. Most businesses take 42 hours.
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