Airlock Digital vs Microsoft Defender for Business for Australian SMBs in 2026: Which Control Comes First?

Winner: it depends on the job — these are complementary controls, not rivals. Defender for Business detects and responds to threats. Airlock Digital stops unapproved software running at all. Most Microsoft 365 businesses should switch on Defender first. It costs AU$4.50/user/month ex GST, or nothing extra on Business Premium. Choose Airlock when a tender, insurer or contract demands genuine Essential Eight application control. Mature organisations run both.

Last reviewed: 12 June 2026 by Adam.

Editorial guidance, not security advice. This comparison is independent editorial opinion to help you shortlist tools. It is not cyber security, legal or compliance advice. No single product delivers Essential Eight compliance on its own. Engage a qualified IT provider, MSP or security consultant before deploying either tool.

One honesty note before anything else. Airlock Digital is not an AI product. Its engine is deterministic, rule-based application allowlisting — no machine learning decides what runs. Our Airlock review flags this openly, and this comparison does too. We include it because that determinism is exactly what makes it effective. Defender for Business, by contrast, genuinely is AI-driven — machine-learning detection with automated response.

Quick comparison

What both tools actually do

These two products answer different security questions, and the difference matters more than the one-point score gap.

Airlock Digital, built in Adelaide and designed around the ACSC's Essential Eight from day one, does application control. Nothing runs on a protected machine unless it matches an approved trust rule — by cryptographic hash, publisher signature, file path or parent process. Everything else is denied by default. That delivers the first Essential Eight mitigation strategy, the one the ACSC rates among the most effective, to Maturity Level 3 — the top tier. It covers Windows, macOS and Linux, and runs on-premise, in the cloud, or fully air-gapped.

Microsoft Defender for Business is endpoint detection and response for businesses under 300 users. It is the core of Microsoft's enterprise Defender for Endpoint engine, repackaged with a setup wizard. It uses machine learning and cloud analysis to spot malware and suspicious behaviour. Its "automatic attack disruption" can isolate a compromised device on its own, before a human looks. It covers Windows, Mac, Android and iOS, up to five devices per user licence.

Put plainly: Airlock prevents unapproved code from ever executing. Defender watches what executes and reacts. One is a locked door; the other is an alarm system with a guard. A serious security posture wants both, which is why our verdict splits by business type rather than crowning a single product.

Pricing in Australia

Defender for Business is the easy one to price. Microsoft's Australian product page lists it at AU$4.50/user/month, paid yearly, ex GST — 10% GST is added at checkout. Already on Microsoft 365 Business Premium at AU$32.90/user/month, paid yearly, ex GST? Then Defender for Business is in your subscription at no extra cost. Many Australian SMBs are paying for it right now and haven't switched it on. Servers need an add-on at US$3 per instance/month — about A$4.65 at ~1.40 AUD/USD, with GST added at checkout on Microsoft's AU billing. GST-registered businesses can generally claim the GST back as an input tax credit; confirm with your accountant.

Airlock is genuinely quote-only. There is no public per-endpoint price, and the major third-party listings all show "custom" or "contact vendor". We won't invent a figure. What we can say: Airlock is an Australian company, so quotes come in AUD with 10% GST added. If you're GST-registered, that GST is generally claimable as an input tax credit. Pricing is sold per endpoint, typically through partners and MSPs, and scales with your environment. Get a written quote before you budget — and ask for the support SLA in writing at the same time, because Airlock doesn't publish one.

The pricing asymmetry is real friction. You can budget Defender from a web page in two minutes. Airlock requires a sales conversation. That's a fair mark against it, and it's why Airlock's Value for Money scored 4/5 against Defender's 5/5 in our reviews.

Where Airlock Digital wins

• The Essential Eight's hardest control, done properly. Airlock claims to be the only allowlisting vendor meeting the ACSC's Application Control strategy at Maturity Level 3 — workstations, servers and driver control. Defender's attack surface reduction rules only partially address application control, and custom ASR rules need Intune.
• Deterministic, deny-by-default protection. Nothing unapproved runs, full stop. A deterministic control can't be fooled the way an ML classifier can. Ransomware and unknown malware are stopped by design, not by detection.
• Sovereignty and air-gap capability. On-prem or air-gapped deployment keeps all execution and policy data onshore and under your control. Airlock's stated philosophy is that organisations own trust decisions, not a vendor cloud. Defender's data can sit in Australian Azure regions, but it remains a vendor-cloud service.
• Australian-built for Australian doctrine. Adelaide-founded in 2013, Adelaide-headquartered, designed around the Essential Eight rather than retrofitted to it. For tender and insurer conversations, that mapping is native.
• Linux coverage in the base product. Airlock's agent covers Windows, macOS and Linux. Defender for Business needs the server add-on to reach Windows and Linux servers.

Where Defender for Business wins

• Price and transparency. AU$4.50/user/month ex GST on a public AUD pricing page — or effectively free inside Business Premium. Airlock can't be comparison-shopped at all.
• Genuine AI-driven automation. AI-powered EDR with automatic attack disruption and automated investigation contains threats without a security team awake at 2am. Airlock has no detection or response layer — that's not its job.
• Far lighter to switch on. A basic Defender deployment uses a setup wizard and Microsoft's recommended defaults. Airlock needs weeks of audit-mode baselining before enforcement, plus ongoing allowlist administration.
• Broader threat coverage per dollar. Next-gen antivirus, EDR, attack surface reduction and vulnerability management in one licence. Airlock does one mitigation; Defender contributes to four of the eight Essential Eight strategies.
• Mobile devices covered. Android and iOS are in scope, five devices per user. Airlock's agent is desktop and server only.

Which to pick — decision framework

If you run Microsoft 365 and just need to be safer this month: switch on Defender for Business. You may already own it inside Business Premium. Get an IT partner to configure it and watch the alerts.

If a government tender, cyber-insurance policy or supply-chain contract demands Essential Eight application control: that's Airlock's home ground. Defender's partial, Intune-dependent ASR coverage won't satisfy a Maturity Level 2 or 3 assessment the way purpose-built allowlisting does. Budget for an MSP-supported rollout over weeks, not hours.

If you're a solo, non-technical operator: Defender via an IT partner, full stop. Airlock's deny-by-default model needs careful administration you won't have time for.

If you're an organisation with real IT maturity and real obligations: run both. Airlock denies what shouldn't run; Defender detects and disrupts what does. They cover different Essential Eight ground and don't duplicate each other.

The verdict

For the default reader of this publication — a Microsoft 365 business under 300 users with no compliance mandate — the winner is Defender for Business. The reason is simple. It's enterprise-grade detection at AU$4.50/user/month ex GST, possibly already paid for, with Australian data hosting available. Switching it on is the highest-value security move most Australian SMBs can make this quarter.

But when the job is the Essential Eight's first control, the winner flips. Airlock Digital is the benchmark for application control in Australia, and Defender is not a substitute for it. Airlock holds our category Top Pick for application allowlisting on exactly those grounds. It earned 22/25 with a perfect 5/5 Australian Fit; Defender earned 21/25, also with 5/5 Australian Fit. Both pass the Australian Fit gate, so both wear five stars honestly.

The truthful summary is that this is a both/either question, not a versus question. Unless you have an allowlisting mandate, start with Defender. When the mandate arrives — and for more Australian businesses each year, it does — add Airlock. Either way, deploy with a qualified IT partner or MSP. Neither product, alone or together, makes you "Essential Eight compliant" on its own.

Frequently asked questions

Is Airlock Digital or Microsoft Defender for Business better for Australian businesses?

Defender for Business, for most. It is the default for Microsoft 365 businesses under 300 users, at AU$4.50/user/month ex GST or included in Business Premium. Choose Airlock Digital when a tender, insurer or contract demands Essential Eight application control — that is its home ground. Mature organisations run both, because the two tools do different jobs.

How much do Airlock Digital and Defender for Business cost in Australia?

Defender for Business costs AU$4.50/user/month, paid yearly, ex GST, with 10% GST added at checkout. It is also included at no extra cost in Microsoft 365 Business Premium at AU$32.90/user/month ex GST. Airlock Digital is quote-only — no public per-endpoint price exists. As an Australian company, its quotes come in AUD with 10% GST added.

Can Airlock Digital or Defender for Business keep data in Australia?

Yes, both can — in different ways. Airlock Digital deploys on-premise or fully air-gapped, keeping all execution and policy data onshore and under your control. Its vendor-hosted cloud region is unpublished. Defender for Business can store data in Australian Azure data centres via tenant provisioning, though it remains a vendor-cloud service.

Is Airlock Digital an AI product like Microsoft Defender for Business?

No. Airlock Digital's engine is deterministic, rule-based application allowlisting — no machine learning decides what runs, and that determinism is exactly what makes it effective. Defender for Business genuinely is AI-driven: machine-learning detection, automated investigation and automatic attack disruption that can isolate a compromised device before a human looks.

How do Airlock Digital and Defender for Business score under The AI Directory's methodology?

Airlock Digital scores 22/25 and Defender for Business 21/25, both with a perfect 5/5 Australian Fit. Both pass the Australian Fit gate, so both wear five stars honestly. Airlock holds our category Top Pick for application allowlisting. The one-point gap reflects pricing: Airlock's quote-only model scored 4/5 on Value for Money against Defender's 5/5.

Read next

• Full review: Airlock Digital Review Australia 2026
• Full review: Microsoft Defender for Business Review Australia 2026
• Category guide: Best AI Cybersecurity Tools for Australian Small Businesses (2026)

Sources

All facts in this comparison come from our two source reviews, each verified against primary vendor sources with Wayback snapshots:

1. The AI Directory Australia — Airlock Digital Review Australia 2026 (Ghost-Ready/review-airlock-digital-australia-2026-06-07.md) — score 22/25, Australian Fit 5/5; primary sources verified 7–8 June 2026 (airlockdigital.com product, Essential Eight, allowlisting, about, privacy pages; ReversingLabs; Forrester TEI; Software Finder pricing listing).
2. The AI Directory Australia — Microsoft Defender for Business Review Australia 2026 (Ghost-Ready/review-microsoft-defender-for-business-australia-2026-06-07.md) — score 21/25, Australian Fit 5/5; primary sources verified 7–8 June 2026 (Microsoft AU product page with AU$4.50 and AU$32.90 ex-GST pricing; Microsoft Learn FAQ and data-storage documentation; ACSC Essential Eight publications).

Exchange rate used for the USD-only server add-on: US$1 ≈ A$1.40 (September 2026 working rate). GST basis is stated alongside every price above.

The AI Directory Australia is an independent editorial publication. We don't accept payment for positive reviews. This comparison is editorial guidance, not security, legal or compliance advice. Read our Methodology.