Case Studies & Worked Examples
Realistic ROI walkthroughs for direct mail campaigns across the verticals PostKnock serves. Use these as planning models for your own campaigns.
All case studies on this page are worked examples, not real customer testimonials.
PostKnock launched in 2026 and we don't yet have a roster of customers we can name publicly. Rather than fabricate testimonials, every case study below uses a clearly hypothetical practice or company profile, combined with industry-benchmark response rates from sources like the ANA Response Rate Report and the USPS Household Diary Study, to model what a typical campaign returns. Real testimonials require real customer permission — we will publish those as soon as our first customers give us the green light. Until then, these worked examples are designed to help you plan your own campaign math honestly.
PostKnock originals
Dental · Recall ROI
Dental Recall Campaign: 3 Waves, $30K ROI
Hypothetical 4-chair family practice, 600 lapsed patients, 3-wave postcard + phone follow-up campaign at $1,719 total cost. Models 8% cumulative response, 48 reactivated patients, $57,600 first-year revenue, 33:1 ROI.
Read worked example →HVAC · Seasonal Tune-Up
HVAC Spring Tune-Up: 1,500 Customers, $33K Revenue
Hypothetical 8-tech residential operation, 1,500 inactive past customers, 2-wave spring maintenance campaign at $2,469 total cost. Models 75 booked tune-ups, $33K ticket revenue plus $7,560 maintenance plan recurring.
Read worked example →Optometry · Insurance Recall
Optometry Benefits Recall: $19K From 800 Postcards
Hypothetical solo-doctor practice, 800 patients with year-end vision benefits expiring, 2-wave use-it-or-lose-it campaign at $1,363 total cost. Models 6% response, 48 booked exams, $22,700 revenue with multi-pair upsell.
Read worked example →Chiropractic · Care Plan Reactivation
Chiropractic Care Plan: 5% of Lapsed Patients in 90 Days
Hypothetical solo-DC practice, 400 patients lapsed mid-care-plan, 3-wave reactivation campaign at $1,245 total cost. Models 5% response, 20 reactivated patients, $20K first-year revenue. Includes the conversion call script.
Read worked example →Pest Control · Annual Renewal
Pest Control Annual Renewal: $22K From 1,000 Customers
Hypothetical 4-tech residential pest control operation, 1,000 expiring annual contracts, 2-wave continuity-focused renewal campaign at $1,679 total cost. Models 50 renewals at $450 average, $25,500 revenue with 30% add-on attach.
Read worked example →Healthcare
Veterinary · Wellness Recall
Veterinary Wellness Recall
2-vet small-animal hospital, 1,200 pets overdue for annual wellness, 2-wave postcard + reminder call campaign. Models 5.8% response, 70 booked exams, $32,200 revenue at 4.5x ROI.
Read composite case study →Physical Therapy · Progress Restart
PT Progress Restart
Solo-clinician PT practice, 280 patients who stopped attending mid-plan, 3-wave "finish what you started" campaign. Models 4.6% response, 13 restarts, $11,830 revenue at 3.4x ROI.
Read composite case study →Audiology · Annual Hearing Test
Annual Hearing Test Recall
Solo audiologist, 480 patients overdue for annual hearing test, 2-wave recall + reminder call. Models 4.1% response, 20 booked tests, $14,800 revenue at 5.6x ROI.
Read composite case study →Orthodontics · Free Consult Blitz
Free-Consult Acquisition
Solo orthodontist, 800-piece neighborhood farm to families with school-age kids, 2-wave free-consult campaign. Models 4.5% response, 18 started cases, $86,400 revenue at 25x ROI.
Read composite case study →Dermatology · Skin-Cancer Screening
Annual Skin-Cancer Screening
2-derm practice, 600 patients overdue for annual skin check, 2-wave clinical recall. Models 5.2% response, 31 booked screenings, $9,300 revenue plus 4 high-LTV referrals at 2.7x ROI.
Read composite case study →Podiatry · Diabetic Foot Care
Diabetic Foot-Care Recall
Solo podiatrist, 240 diabetic patients overdue for protective foot exam, 2-wave clinical recall + reminder call. Models 6.1% response, 15 visits, $5,100 revenue at 1.9x ROI.
Read composite case study →Home Services
Plumbing · Water-Heater Replacement
Water-Heater Replacement
5-tech residential plumber, 1,400 past-customer households with water heaters 8+ years old, 2-wave proactive replacement campaign. Models 2.0% response, 28 replacements, $58,800 revenue at 14x ROI.
Read composite case study →Landscaping · Spring Cleanup
Spring Cleanup Acquisition
Owner-operator landscaping crew, 1,200-piece neighborhood farm in established suburbs, 2-wave spring-cleanup campaign. Models 2.0% response, 24 cleanups, $9,600 revenue at 4.4x ROI plus seasonal renewal pipeline.
Read composite case study →Roofing · Post-Storm Response
Post-Storm Hyperlocal Response
Owner-operator roofer, 900-piece post-hailstorm hyperlocal campaign within 72 hours of event. Models 6.8% response, 28 inspections, 12 jobs at $98,400 revenue, 31x ROI.
Read composite case study →Pool Services · Spring Opening
Spring Opening Recall
4-tech pool service operation, 800 past spring-opening customers, 2-wave seasonal recall + reminder call. Models 2.8% response, 22 openings, $9,900 revenue at 4.7x ROI.
Read composite case study →Cleaning · New-Mover Welcome
New-Mover First-Time Customer
3-team residential cleaner, 950-piece monthly new-mover farm in suburban core, 2-wave welcome campaign. Models 2.8% response, 27 first cleans, $5,940 revenue at 2.6x ROI plus recurring pipeline.
Read composite case study →Auto
Auto Repair · Overdue Service
Overdue Service Reminder
5-bay independent shop, 1,500 customers overdue on factory-recommended service, 2-wave personalized recall. Models 1.2% response, 18 returns, $9,360 revenue at 2.9x ROI plus pipeline.
Read composite case study →Oil Change · Quarterly Reminder
Quarterly Mileage Reminder
2-bay quick-lube, 2,000 past customers due for next oil change, 2-wave reminder + add-on upsell. Models 1.6% response, 32 visits, $2,560 revenue + tire and air-filter attach at 1.4x ROI.
Read composite case study →Smog Check · Renewal Proximity
Registration Renewal Proximity
California smog station, 1,800 vehicles approaching biennial registration-renewal smog check, 2-wave timing-targeted campaign. Models 2.2% response, 40 visits, $2,200 revenue at 1.0x first-visit ROI.
Read composite case study →Finance
Real Estate · Just-Listed Farm
Just-Listed Neighborhood Farm
Solo agent, 600-home neighborhood just-listed farm with 3-postcard cadence. Models 0.8% direct response, 4 buyer leads, 2 listing conversations, projected 1 listing at $11K commission, 3.4x ROI.
Read composite case study →Insurance · Auto Renewal Recall
Auto Policy Renewal Proximity
Independent insurance agency, 350 auto-policy holders 60 days from renewal, 1-wave proactive re-shop campaign. Models 11.4% response, 40 re-quote conversations, $9,600 retained-premium uplift at 11x ROI.
Read composite case study →Tax & CPA · Q4 Planning Blitz
Q4 Year-End Planning
Solo CPA, 220 past tax-prep-only clients, 1-wave Q4 advisory recall. Models 4.6% response, 10 planning engagements at $4,800 revenue plus 4 conversions to recurring advisory at projected $14,400 ARR.
Read composite case study →Personal & Wellness
Med Spa · Membership Relaunch
Med Spa Membership Relaunch
4-room med spa, 320 lapsed members, 2-wave relaunch with phone follow-up. Models 3.4% response, 11 reactivations, $9,240 first-year revenue at 3.2x ROI.
Read composite case study →Hair Salons · Color Client Winback
8-Week Color Client Winback
4-chair salon, 380 lapsed color clients past their 8-week cycle, 2-wave winback with stylist-specific personalization. Models 3.2% response, 12 rebooks, $2,640 revenue plus retention pipeline.
Read composite case study →Yoga Studios · New-Mover Welcome
New-Mover First Class Free
Single-location yoga studio, 800-household monthly new-mover farm in 3-mile radius, 1-wave first-class-free welcome. Models 3.4% response, 27 first-class redemptions, 11 monthly-membership conversions at $1,177/mo recurring.
Read composite case study →Martial Arts · Kids Trial Class
Kids Trial Class
Single-school martial arts academy, 600-household neighborhood farm targeting families with kids 5-12, 2-wave trial-class campaign. Models 2.8% response, 17 trials, 9 enrollments at $129/month recurring.
Read composite case study →Dance Studios · Fall Registration
Fall Registration Open House
Multi-program dance studio, 700-household family farm + past-student recall, 2-wave fall-registration campaign. Models 3.6% response, 25 open-house RSVPs, 16 enrollments at $1,840/mo recurring.
Read composite case study →Personal Training · 6-Week Challenge
6-Week Body Transformation
Solo personal trainer, 500-piece hybrid lapsed-client + warm-prospect list, 2-wave 6-week-challenge campaign. Models 2.8% response, 14 challenge sign-ups at $399 each = $5,586 revenue plus 6 conversions to recurring training at 11x ROI.
Read composite case study →Want to model your own campaign?
Plug your customer count, average ticket, and target response rate into our ROI calculator to see what a campaign like these returns for your business.