The Lost Inquiry Calculator: what unanswered emails, forms and marketplace leads cost you per year

The short version: an inquiry is worth your close rate times your average booking, and the cost of an unanswered inbox is that value multiplied by the inquiries nobody carried to an answer. Leadferno's 2024 test of 225 small-business contact forms found 42.6% got no reply at all⁵. For a consultant with 8 inquiries a month, a 25% close rate and $6,000 projects, that default alone puts about $61,000 a year in the unanswered pile. The rest of this article shows the formula, the worked cases, and the point where the defaults break.

A Thumbtack pro did this math by hand#

The thread on the Thumbtack Community forum was titled "What % of 'direct leads' actually end up booking you?"¹ The pro who started it had counted. About 30 direct leads had come in. In the pro's words, "every single one has just vanished after 1 or 2 messages."

Others answered with their own ledgers. One had been charged $78 two days earlier "for a direct lead and the person doesnt even respond to a text." Another summed up the year in one line: "for every $5 I make, I pay $3."¹ The thread's poll drew 13 votes; 9 of them (69%) picked "Most of my direct leads never reply, but I occasionally book one."¹

What none of them had was the other half of the ledger: how many of those leads they had answered within the hour, how many they had written to a second time, and what each one would have been worth. They had a cost per lead. They did not have a value per inquiry.

Why existing lost-lead calculators don't fit written inquiries#

The lost-leads calculators that rank today were built for phones. Footbridge Media's, published 18 June 2025 for home-service trades, asks for three inputs: "Missed Calls Per Week," "Estimated Close Rate (%)" and "Average Job Value ($)."² Others we found, for real estate and for lead response time, are also built around calls.

A written inquiry fails differently from a call. A call is missed or answered in the moment. An email or form inquiry can be answered the next afternoon, answered once and never followed up, or answered by an auto-reply that says nothing. The money leaks at each of those points, and a missed-call formula only sees the first.

The wedding trade has asked the right question without doing the arithmetic. Indigo Digital wrote in August 2026: "if even one in twenty qualified enquiries is lost purely because of a slow or absent response," the answer is "very often tens of thousands of dollars a year." The article shows no worked numbers³.

Vendors who pay for leads feel the gap most. A photographer's February 2025 BBB review, collected by The Knot Whistleblowers advocacy site, described an $8,000 annual contract that produced "one elopement and two weddings," with "No clear way to track ROI."⁴ Nobody in that review, or in the Thumbtack thread, could say how many inquiries went unanswered and how many went quiet after one reply. That is the spreadsheet that was missing.

How the Lost Inquiry Calculator works#

The Lost Inquiry Calculator values every inquiry the same way, then counts three groups. The value per inquiry is your close rate on answered inquiries times your average booking. The three groups are the ones a written inbox actually produces.

1. Line A: never answered. Inquiries per year × share never answered × value per inquiry. Default share: 42.6% (Leadferno, 225 small-business forms, June 2024)⁵.
2. Line B: answered once, no follow-up. Inquiries per year × share answered × share given one attempt only × value per inquiry × 0.5. Default: 57.4% answered and 65.5% one attempt only⁵. The half-weight is our assumption, explained below.
3. Line C: the floor. Inquiries per year × 5% × value per inquiry. This is Indigo's "one in twenty" framing³, written out as arithmetic. It is the number to quote when someone says your estimate is too high.

Line A is the exposure from silence. Line B is the exposure from stopping too early. Line C is a floor that assumes almost everything else is fine.

Why Line B is half-weighted#

An inquiry that got one reply is not lost in the way an unanswered one is. Some of those customers book after one message. No public study measures how many inbound small-business inquiries would have booked with a second message. The nearest evidence is outbound: in a 2026 Belkins analysis of 7.53 million B2B emails, 58.6% of replies came after the first message¹⁰. That is cold email, not an inbound inquiry, so we use it only to justify a round half-weight rather than a full one. If your own data says otherwise, change it.

Where the defaults broke: the venue that "lost" $330,000#

The first time we ran the worksheet on a venue preset, it produced a number nobody would believe. The inputs were defensible. Indigo Digital's benchmark guide says about 1 in 5 qualified venue enquiries books, and that a venue booking 60 weddings a year needs about 300 qualified enquiries⁶. The Knot's 2026 Real Weddings Study, 10,474 couples, puts the average reception venue at $12,900⁷. That gives $2,580 of expected value per qualified inquiry.

Then Line A ran: 300 × 42.6% × $2,580 ≈ $329,700 a year of unanswered inquiries. For a venue whose 60 bookings bring in about $774,000, that means ignoring 128 qualified couples a year while still booking 60. That may be true of some venue somewhere. The default cannot tell you whether it is true of yours.

The failure was not in the arithmetic. It was in the borrowed rate. Leadferno tested home-service, professional-service and medical businesses that ranked in the top 10 of Google's local results, and tracked replies by email, phone and text for three weeks⁵. None of them were wedding venues. A venue with a dedicated sales coordinator may answer 95% of inquiries; a solo photographer shooting every Saturday may answer 60%. The 42.6% is a measured rate for someone else's inbox.

A second snag sat inside Line B. Leadferno reports "65.5% making just one attempt" without stating the denominator⁵. Since 42.6% got nothing, 65.5% cannot be a share of all inquiries, or the two would add to more than 100%. We read it as a share of the businesses that replied. That is an inference, and the worksheet labels it as one.

Worked examples: venue, photographer, consultant#

The presets below use sourced prices and labelled assumptions. Close rates other than the venue's are assumptions, because we found no reliable public close rate for photographers or consultants. Inquiry volumes are illustrations.

Values rounded to the nearest $100. Consulting Success's 2026 study of nearly 1,000 consultants gives illustrative project tiers of $6K, $12K and $24K and reports 52% of specialists charge $10K+ per project⁹; the $6,000 tier is the conservative choice.

Read the table by column, not by row total. Line A and Line B overlap with the floor and should not be added to it. For the consultant, the useful sentence is: at default rates, about $61,000 a year sits in inquiries that never got a reply, another $27,000 in inquiries that got one reply and nothing else, and even the floor is $7,200.

We left accountants, coaches and tutors out of the presets on purpose. The fees we found for them were single anecdotes or uncited ranges, and a preset built on those would look more precise than it is. Use your own average fee.

The Lost Inquiry Calculator worksheet#

The worksheet below is the whole calculator. It fits in one spreadsheet tab, and every default has a "your number" column beside it, because the venue run showed what happens when the defaults stay in.

Cell	Input or line	Default	Your number	Formula
B1	Written inquiries per year (email, forms, listing and marketplace emails)	none	count last 90 days × 4	input
B2	Close rate on answered inquiries	venue 20%; others: your own	booked ÷ answered	input
B3	Average booking value ($)	The Knot 2026 by category; Consulting Success tiers	from your price list	input
B4	Value per inquiry ($)			=B2*B3
B5	Share never answered	42.6% (Leadferno 2024)	your count ÷ B1	input
B6	Share of answered given one attempt only	65.5% (Leadferno 2024; denominator inferred)	your count ÷ answered	input
B7	Line A: never answered ($/yr)			=B1*B5*B4
B8	Line B: answered once, no follow-up ($/yr)	half-weight 0.5 (assumption)		=B1*(1-B5)*B6*B4*0.5
B9	Line C: floor ($/yr)	5% (Indigo "one in twenty")		=B1*0.05*B4
B10	Sanity check			If B7 > one year's revenue, re-count B5

Sources for defaults: Leadferno, 225 forms, June 2024⁵; Indigo Digital, August 2026³⁶; The Knot, 2026⁷; Consulting Success, 2026⁹. Line B's half-weight is a Valet assumption.

How to get your own numbers in an afternoon#

The worksheet's defaults are there to start the conversation; your last 90 days end it. The counts that matter are short, and most owners can pull them from Gmail searches and a sent folder.

1. Count inquiries by source. Search for form notifications, listing and marketplace lead emails, and direct inquiries. Write the 90-day total in B1 (times four for a year).
2. Mark each one. Never answered; answered once with no follow-up; answered more than once; booked. Leave nothing unmarked; an inquiry you are unsure about is usually "never answered".
3. Compute your close rate. Booked ÷ answered. This is the most honest value of an inquiry you have.
4. Put the three lines side by side. If Line B is larger than Line A, your problem is follow-up, not first replies. In Pied Piper's 2026 mystery shop of 3,211 home-services inquiries, 72% got no follow-up at all¹¹, so this is a common result.

The full method, with Gmail search strings and the five outcome labels, is in the Lost Lead Audit. If Line A is your largest line and form inquiries are a big share of it, check whether your form is delivering at all; the contact-form leak covers that. If Line B dominates, how many times to follow up sets out a capped standard.

What the Thumbtack pro could have known#

The pro with 30 vanished direct leads knew the cost per lead to the dollar. With this worksheet the pro would also know whether those leads went quiet after the first message or the second, and what each was worth at the pro's own close rate. That turns "are these leads fake?" into a question the ledger can answer: how many got a second message with something new in it, and how many of those booked.

We do not yet have a published distribution of those outcomes for written inquiries. Valet is collecting it as inquiries move through the Valet Inquiry States, and the defaults in this worksheet will be replaced with measured rates, with their method, when the sample supports it.

Where Valet fits#

Valet answers email, website-form and listing inquiries from the owner's own price list, packages, calendar and policies, offers and holds real times, and follows up at most twice by default, each time with something useful. Every inquiry has a state, a next step and a time, so Lines A and B stop being estimates and become counts. Money questions, complaints and contracts wait for the owner.

If you would rather not build the spreadsheet, the free lead check runs this calculation on real messages: forward 10–20 recent inquiries, or show them on a call, and see what went unanswered, what stopped after one reply, and what it was worth.