About
Encryption was the assignment. Tax prep was the application.
SealedReturn started with a simple question: which categories of consumer software handle the most sensitive personal data, and which ones still haven't been built with end-to-end encryption?
Tax prep was the answer that surprised us most. Every year, 60+ million Americans hand over their full tax life — SSN, wages, bank account, dependents, business income, real estate holdings — to TurboTax, H&R Block, or one of a dozen smaller players. None of them encrypts client-side. All of them could, in normal operation, read your data. Their employees can. Their cloud provider can with a court order. Their breach attacker can. Their next acquirer can.
We built SealedReturn so that we cannot. Your tax photos, your SSN, your Schedule C — encrypted on your device with libsodium, before they ever touch our network. The server stores ciphertext only. We cannot read your data, even if a state actor compels us. By design.
The founder
Iskra Astudillo.
Iskra Astudillo · founder
Iskra is a multi-business operator and the founder of the Berylus group of companies (short-term rental cohosting, AccountItUp multi-LLC accounting, Elite Health Essentials supplements, and SealedReturn). She files her own taxes through SealedReturn — and publishes the journey on LinkedIn and X.
Iskra is named publicly because the legal research is clear: founder accountability is a higher-leverage trust artifact than a SOC 2 logo could ever be. If something goes wrong, she's the one you can talk to — not a support ticket queue.
Reach her: hello@sealedreturn.com
Our principles
Five non-negotiables that shape every decision.
Client-side encryption is the default
Not an upsell. Not a "Pro" feature. Every paid tier uses libsodium client-side encryption. The Privacy Plus tier (+$10) extends to client-side LLM extraction via WebGPU.
We will never e-file (Path A by design)
E-filing requires IRS Authorized e-file Provider status, Pub 1345 compliance, state ERO registration, and an entirely different liability surface. We chose to never go there. You sign and file your own return.
Open-source the encryption layer
The cryptography that powers SealedReturn is being published on GitHub under MIT. Anyone can read it, audit it, fork it. This is the highest-leverage trust artifact at zero cost.
No "free" tier. No upsells. No dark patterns.
Three tiers, three published prices. State return always included. No checkout-time pressure. We can afford to do this because $39 is profitable on day one.
Founder accountability over corporate veil
Iskra is named on this site, in the WISP, and on every contract. If a customer has a problem, there is a real person to escalate to. SOC 2 won't replace that — and it doesn't have to.
Real cryptography, not theater
We use audited primitives (libsodium, Argon2id, XChaCha20-Poly1305). We don't roll our own crypto. We don't say "bank-level encryption" because that phrase means nothing.
The Berylus family
Sister companies.
See encryption + AI vision in 60 seconds.
Try the live demo. No signup. We encrypt a sample W-2 in your browser, run real AI extraction, and generate a Form 1040 PDF — so you can see the moat with your own eyes.