On usedby, 20 companies use Rillet and 28 use Zest. No company is listed with both yet. Zest leads among the Banking & Mortgages companies on usedby that use either tool.Latest check Oct 8, 2026: 38 of 48 public lines checked. Counts include every proof level, job-post signals included. Companies named on both have a confirmed or observed line on each side.
Who uses Rillet, Zest, or both
Every company with a public proof for at least one of the two tools.
20
use only Rillet
0
companies use both
28
use only Zest
20 companies use only Rillet, 28 use only Zest and 0 use both, out of the 48 companies on usedby that use at least one of them.
Where it lands
Newest customers
No new customer since tracking started on October 8, 2026.
Where it lands
Newest customers
No new customer since tracking started on October 2, 2026.
Who uses both
Companies with a confirmed or observed line on both tools.
Side by side
Facts from our data and from each vendor's public pages. Each line says where it comes from.
Rillet
ZestWhat customers report
Results as the vendor or the customer published them, with the source and the date.
Rillet

Postscript's close is now consistently 3 days.
Postscript
Vendor case study, rillet.com, captured Oct 8, 2026

Zest
No reviewed story for Zest yet.
Questions about Rillet and Zest
Which is used more, Rillet or Zest?
Zest has more customers on usedby: 28 against 20 for Rillet.
Do companies use both Rillet and Zest?
usedby has not found a company with a confirmed or observed line on both Rillet and Zest yet.
Who uses Rillet?
20 companies on usedby, each with the public page that shows it. See who uses Rillet.
Who uses Zest?
28 companies on usedby, each with the public page that shows it. See who uses Zest.
How does usedby count customers?
A company counts when a public page shows it: a vendor's customer page, a case study, a press release or a job post, most saved with a dated capture. Every line is a customer, at one of three proof levels: confirmed, observed or signal (a job post, the weakest). A company is named as using both tools when its lines on both are confirmed or observed.