The short version
Kastle and Sei both run compliant AI voice agents for borrower calls, and both target mortgage. Kastle concentrates on the servicing side — payments, escrow, retention, and early-stage collections — across multiple channels.
Sei runs voice across the whole lifecycle and pairs it with the loan operation. Servicing agents handle payoffs, due-date changes, and FDCPA-compliant hardship calls; origination agents run speed-to-lead and book loan-officer appointments; and the same managed platform underwrites the file with rep-and-warrant-eligible income, automates the Closing Disclosure, and clears post-close QC.
WHAT KASTLE DOES
Kastle provides AI voice agents that automate high-volume borrower servicing calls — payments, escrow, retention, and early-stage collections — across voice, text, email, and webchat.
Sei vs Kastle, at a glance
Comparison based on each vendor's public materials as of June 2026. Competitor capabilities and claims are theirs; we aim to keep this fair and accurate — if anything is out of date, let us know.
Where Sei is different
Voice across the whole lifecycle
Speed-to-lead and 24/7 inbound sales agents, loan-officer appointment booking, and FDCPA-compliant servicing and collections — borrower conversations from first contact through payoff, on one platform.
Rep-and-warrant-eligible income
Income is calculated across W-2, self-employed (Schedule C, K-1, S-corp, 1099), rental, and retirement income, with Fannie Mae Income Calculator integration — so eligible calculations earn representation-and-warranty relief and lower repurchase risk.
Fully managed, end to end
Sei builds, deploys, and runs the agents and workflows for you — from the first sales call through underwriting, closing, and post-close QC. You get outcomes, not a toolkit to configure, typically live in weeks.
Where Kastle fits
- Strong, focused servicing automation across call, text, email and webchat
- Integrations with servicing systems of record, including ICE MSP
- Built for high-volume servicing and payment conversations
When Sei is the better fit
- You want voice on both origination and servicing from one platform
- You also need underwriting, income calculation, closing and QC
- You want 100% call QA against TILA, RESPA, TRID and UDAAP
Frequently asked questions
Yes. Sei’s voice agents handle servicing calls — payments, payoffs, due-date changes, hardships, and FDCPA-compliant collections — and also cover origination, underwriting, closing, and QC on the same managed platform.
Yes. Sei integrates with ICE and other loan-management systems, CRMs, and telephony/CCaaS platforms, with custom integrations supported during onboarding.
Origination sales voice with LO appointment booking, document intelligence and underwriting, income calculation for rep-and-warrant relief, Closing Disclosure automation, and pre/post-close QC.
Sei is SOC 2 Type II and PCI DSS Level 1 certified, deploys in private VPCs, and never trains on your data.
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Sei vs Genesys
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Read comparisonBOOK A DEMO
- Deploy in weeks, not months
- Trained on FDCPA, TCPA, TILA, UDAAP, and RESPA
- SOC 2 Type II and PCI DSS L1 certified
- Integrates with your LOS, CRM, and telephony
