Microsoft Word and Office add-ins for law firms

We build Word, Outlook and Excel add-ins that automate lawyers' daily work inside the tool they already use. No context switching, no yet-another-SaaS to learn, no documents leaving your Microsoft 365 tenant.

The problem: lawyers live in Word, but Word knows nothing about law

Most law firms — from boutique teams to large multi-practice firms — do 60–80% of their daily work in Microsoft Word and Outlook. Contract drafting, redlines, court filings, legal opinions, client correspondence. Yet out-of-the-box Word has no idea that unfair terms exist, that your NDA has a standard library of variants, or that a court filing requires a specific header and a qualified signature.

The result: lawyers copy fragments from previous documents, stitched together from 10 different template versions floating around network drives. Everyone has their own clause folder. Everyone copies "their" version of the NDA. The firm's institutional knowledge lives in partners' heads and in Word files nobody opens anymore.

The solution: an add-in that brings your firm's knowledge into Word

We build add-ins on the Office Add-ins platform (Office.js) — Microsoft's official, modern standard. The add-in appears as a side panel or a ribbon button in Word and gives lawyers access to:

  • a central library of clauses, templates and variants (with metadata: which client, which context, last updated by whom)
  • document generators driven by guided questions ("NDA wizard") — auto-filling parties, dates and choice-of-law clauses
  • an AI assistant that analyses the current document (e.g. flags risky clauses, checks definition consistency, finds broken cross-references)
  • integration with your practice management system (matter, client, billing) — no manual re-keying
  • compliance checklists (GDPR, EU AI Act, sector-specific) built into the document workflow

What we build — example features

Clause & template library

A central clause base (liquidated damages, NDA, jurisdiction, GDPR, IP, work product…) with variants, tags, metadata and change history. A lawyer inserts a clause in two clicks instead of hunting for "the best version" across 12 folders.

Contract wizard (document automation)

Structured forms that assemble a contract step by step from modular building blocks. Ideal for repeatable document types: NDAs, employment contracts, terms of service, commercial agreements, legal opinions.

AI assistant in the side panel

Real-time document analysis: risky clause detection, definition checks, drafting suggestions, summaries. The AI runs in your infrastructure — see our AI systems for law firms.

Practice system integration

The add-in automatically pulls matter, client and document numbering data from your practice management system or CRM. When the work is done, it files the document in the right place with the right metadata.

Numbering and cross-references

Smart clause numbering, cross-reference validation ("does Section 5(3) actually exist?"), automatic tables of contents that follow court formatting conventions.

Email and Outlook

Outlook add-ins: correspondence templates, automatic matter metadata on outgoing mail, classification of incoming messages by case reference, SLA tracking for client responses.

Technology: clean Microsoft stack

We build add-ins with Office.js (Microsoft's official SDK), TypeScript, React and Fluent UI components, with the manifest in Microsoft's unified Microsoft 365 format. Where a backend is needed, we host it on Azure Functions or Azure App Service inside your tenant — so documents never leave your organisation's Microsoft 365 boundary.

Distribution: Centralized Deployment via the Microsoft 365 Admin Center (for internal rollouts) or AppSource (for commercially distributed products). Updates are automatic — no per-laptop installers.

When building your own add-in makes sense

It makes sense if:

  • you produce repeatable document types dozens of times a month (NDAs, framework agreements, opinions, filings)
  • the knowledge of "how it should look" is scattered across folders, emails and partners' heads
  • you currently rely on VBA macros and they frustrate you (fragile, blocked on Macs, everyone has their own copy)
  • your IT policy forbids sending documents to external CLM SaaS tools (DocuSign CLM, Ironclad) — but you want that functionality inside Microsoft 365
  • you want to distribute a commercial product to other law firms (as a LegalTech vendor)

It does not make sense if: you need functionality Word structurally cannot deliver (e.g. a complex multi-party review/approval workflow) — then a better idea is a dedicated web application with Word attached as the editor.

How a project runs — step by step

  1. Discovery (1–2 weeks). We observe 3–5 lawyers working on real documents. We identify the pain and the wasted time, and map your current stack (practice system, clause libraries, AI tools). The result is a prioritised feature backlog and an MVP quote.
  2. MVP (4–8 weeks). We build a working add-in with 1–3 key features, distribute it to a pilot group, and iterate on real usage.
  3. Rollout (2–4 weeks). Centralized Deployment across the organisation, user documentation, training, a support channel.
  4. Growth and maintenance. New features, updates for new Office versions, integrations with new systems. An SLA maintenance contract is available.

Security and confidentiality

We work with documents covered by legal professional privilege. Standard assumptions of every project:

  • Document data does not leave the client's Microsoft 365 tenant unless it is a conscious architectural decision backed by a risk analysis.
  • No shadow IT — no free AI services, external translators or "public" configuration stores.
  • Access logging, with optional integration into your SIEM.
  • Compliance: GDPR, DORA for financial-market entities, sector-specific regulations as applicable.
  • Code review on our side + an optional client-side audit before production rollout.

What it costs

Pricing depends on scope, but for orientation: a typical add-in MVP for a law firm (clause library + one document wizard + a simple backend integration) is in the range of €10,000–30,000 net for the first production rollout. Larger projects (with AI, multi-system integrations or AppSource distribution) are quoted individually after discovery.

Every quote covers a concrete scope of features and a timeline — we sell outcomes, not hours.

Frequently asked questions

How is a Word add-in different from VBA macros?

VBA macros are tied to a specific document or template, have limited permissions, and most IT administrators block them by default. Add-ins built with the Office Add-ins platform (Office.js) are deployed centrally through the Microsoft 365 Admin Center or AppSource, run in Word on Windows, macOS and Word for the web, and can safely call external APIs. For a law firm this means one version of the add-in for every lawyer — instead of dozens of local macro copies in different versions.

Does the add-in send our documents to external servers?

That is a design decision — and most often it does not. For tasks like inserting clauses, generating tables of contents or checking cross-references, everything runs locally in the Office runtime. Where a backend is genuinely needed (e.g. AI analysis), we route data to an approved backend inside your own Azure / GCP / VPC tenant, with full access logging. We can also build an "offline-first" add-in that keeps even its configuration in your organisation's SharePoint.

How long does a rollout take and how do lawyers get the add-in?

We usually deliver a working MVP in 4–8 weeks. Distribution inside your organisation is a few clicks in the Microsoft 365 Admin Center via Centralized Deployment — the IT administrator assigns the add-in to a chosen user group and it automatically appears in the Word ribbon at the next launch. Updates are equally painless: no installers, no "walking desk to desk".

Will it work on Macs and in Word for the web?

Yes — if we build it on the Office Add-ins platform (Office.js), one codebase runs in Word/Excel/Outlook on Windows, macOS, iPad and in the browser. That is the fundamental difference from legacy COM/VSTO add-ins, which are Windows-only. We verify your business requirements against the Office manifest up front and flag any feature that is platform-specific.

Can you integrate the add-in with our practice management system?

Yes — it is a frequent requirement. We connect add-ins to practice management and document management systems via their APIs, to clause libraries (e.g. internal SharePoint collections), to e-signature providers and to public company registers. See our system integrations service for more.

Have an idea for an add-in for your firm?

Tell us which tasks in Word or Outlook eat the most of your time. Within 1–2 business days we will come back with a proposed approach and an initial MVP quote.

Book a consultation →