Keep every property compliant.

Connect your property data. Automate your workflows.

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  • No credit card needed
  • Setup in 2 minutes
  • Cancel any time
What is MillOS

The Agentic Operating System for your
property portfolio

Certificates
Gas Safety certificate preview with identifying details redacted
Gas Certificate
Renewal flow starts in 120 days

Stay ahead of renewals.

Accounting
Property spending · Jan–Jun
£3,540
Maintenance, certificates & services
0400800JanFebMarAprMayJun
Latest expense
Gas Safety · £85

Keep your finances organised.

£30,000
Avoid penalties for compliance breaches
2 years' rent
Avoid rent repayment for offences
4×
Provide quarterly updates within MTD
31 hrs
Saved time monthly on admin
What MillOS does

AI agents that organise your data and act on your behalf.

  1. You connect once
    • Add your properties
    • Drop in your certificates
    • Link your bank read-only
    • Ten minutes, once.
  2. AI reads it
    • Extracts every expiry
    • Matches rent to the right flat
    • Files each expense and certificate to the right property
  3. AI agents do the work
    • Plans your certificate renewals
    • Coordinates inspection visits with engineers and tenants
    • Reconciles your property ledger
  4. You stay compliant
    • Sends your figures to your accountant each quarter
    • Keeps an evidence pack ready per property
Why MillOS

AI agents for your property. Not another checklist.

Agent 01
Certificates

Certificates pile up. Deadlines slip. Your risk grows.

A checklist tells you what needs doing. MillOS acts: reads incoming certificates, tracks expiry dates and coordinates renewals with engineers and tenants - keeping your records up to date as new documents arrive.

Beyond tracking. Into action.

Gas Safety · Flat 2Renewed ✓
EICR · Flat 5Booked Thu
EPC · Flat 7Valid to 2031
Portfolio score96 / 100
Agent 02
Accounting

Rent arrives. Expenses scatter. Quarter-end becomes a scramble.

A spreadsheet waits for you to update it. MillOS matches rent to properties, organises incoming invoices and prepares figures for your accountant—keeping your books moving throughout the quarter.

Beyond recording. Into preparation.

Monthly expenses
£900Apr£1,200May£1,380Jun
Expenses filed£3,480
Q3 figuresPrepared
MTD packSent to accountant
The MillOS ecosystem

Every property. Every workflow. Connected.

MillOS reads your certificates, tracks their expiry dates and plans renewals. It arranges inspection visits with engineers and tenants, then files the new certificate against the right property.

Testimonials

What UK landlords are saying

Landlords and agents love how MillOS makes a missed deadline impossible.
JW
MillOS caught two Gas Safety certs about to lapse before I'd even noticed. It has genuinely made a missed deadline impossible across my portfolio.
James Whitfield
Portfolio landlord · 34 units
PR
The compliance score per property is the first thing my team checks every morning. Onboarding a new managed property takes minutes now.
Priya Ramesh
Letting agent · Manchester
DO
Per-room rent tracking via Open Banking replaced three spreadsheets. I can see exactly which room is late the day it happens.
Daniel Okafor
HMO operator · Leeds
JW
MillOS caught two Gas Safety certs about to lapse before I'd even noticed. It has genuinely made a missed deadline impossible across my portfolio.
James Whitfield
Portfolio landlord · 34 units
PR
The compliance score per property is the first thing my team checks every morning. Onboarding a new managed property takes minutes now.
Priya Ramesh
Letting agent · Manchester
DO
Per-room rent tracking via Open Banking replaced three spreadsheets. I can see exactly which room is late the day it happens.
Daniel Okafor
HMO operator · Leeds
JW
MillOS caught two Gas Safety certs about to lapse before I'd even noticed. It has genuinely made a missed deadline impossible across my portfolio.
James Whitfield
Portfolio landlord · 34 units
PR
The compliance score per property is the first thing my team checks every morning. Onboarding a new managed property takes minutes now.
Priya Ramesh
Letting agent · Manchester
DO
Per-room rent tracking via Open Banking replaced three spreadsheets. I can see exactly which room is late the day it happens.
Daniel Okafor
HMO operator · Leeds
JW
MillOS caught two Gas Safety certs about to lapse before I'd even noticed. It has genuinely made a missed deadline impossible across my portfolio.
James Whitfield
Portfolio landlord · 34 units
PR
The compliance score per property is the first thing my team checks every morning. Onboarding a new managed property takes minutes now.
Priya Ramesh
Letting agent · Manchester
DO
Per-room rent tracking via Open Banking replaced three spreadsheets. I can see exactly which room is late the day it happens.
Daniel Okafor
HMO operator · Leeds
Blog and articles

The latest for UK landlords

Compliance rules, tax changes and accounting playbooks — written by our UK property specialists.
What's next

Your portfolio in your pocket.
Check in anytime.

See what your AI agents are doing and check your property compliance, wherever you are. Everything you need to stay informed, right on your phone.

iOS & Android apps — coming soon. WhatsApp updates and calls from your AI agents are planned too, so you can stay connected without opening the app.
Try for free today →
MillOS
Friday 16 October
9:41
MillOSnow
Portfolio check-in
Your compliance status, wherever you are.
MillOSnow
WhatsApp update
An update from your AI agents.
MillOSnow
Call from MillOS
Talk to your AI agents on the go.