Top 5 SOFI AI Alternatives for Tax Firms (2026)

Tax firms look for an alternative to SOFI AI for four reasons:

• The waitlist. SOFI’s own product page labels SOFI for Tax “Closed Beta”, access runs through a waitlist, and the pricing page notes that terms for waitlisted firms may differ.
• The price structure. A €399.99 base fee on Small (up to 9 users) or €649.99 on Medium (10–49 users), plus €19.99 per user per month as an expiring token allowance, plus a one-time €3,499.99 onboarding fee. A 9-user firm pays €10,458.79 net in year one.
• Another window. SOFI runs as a web app, an iOS app and, from Medium, an Outlook add-in. It names no Teams integration.
• Tax only, for now. SOFI for Law is announced as coming soon.

Here are the five alternatives that belong on a German tax firm’s shortlist in 2026. For the direct head-to-head, see amaiko vs SOFI AI.

1. amaiko Kanzlei: tax-firm AI inside Microsoft Teams

amaiko Kanzlei is amaiko’s edition for tax firms, and it is available today. It works where your firm organizes its day: in Microsoft Teams. No new tool, no rollout project, no setup fee, no hardware. Each employee connects their own DATEV login and asks the first question in the chat.

DATEV and Haufe in the price. amaiko fetches DATEV data when someone asks and does not mirror the firm’s data stock into a database of its own.

• Rechnungswesen: postings, trial balances and accounts from DATEV’s Rechnungswesen archive. amaiko uploads a Buchungsstapel only after you confirm it, and never finalizes it.
• Lohn: read-only, from gross and net per employee to the official payroll reports as PDF.
• DMS: find and read documents. Writes happen only after you approve a plan, through the Cloud Gateway for DATEVconnect by Riecken.

For tax and employment-law questions, Haufe answers from its own content, using the firm’s own Haufe API key.

The whole workday, with a memory. amaiko Kanzlei reads and drafts across email, calendar, files, Word, Excel and PowerPoint, Teams chats, OneNote, To Do and SharePoint lists, and remembers across conversations what you work on and how you work. That knowledge stays personal.

A sealed tenant for professionals bound by secrecy. amaiko sets the seal at provisioning, in infrastructure, not as an admin toggle, and your data protection officer can verify it. An allowlist of specialists, Microsoft 365 read-only, no background reads of mailboxes, no content in logs or agent traces, no web research. The AI runs on Azure OpenAI with processing in the EU only, and hosting is in Germany on amaiko’s own infrastructure. The data processing agreement carries the confidentiality clauses of § 203 StGB and § 62a StBerG.

The price. €29.91 per user per month billed annually, €37.39 billed monthly. A 9-user firm pays €269.19 a month, against €579.90 on SOFI Small. At 25 users: €747.75 against €1,149.74 on SOFI Medium, plus SOFI’s €3,499.99 onboarding.

Best for: tax firms on Microsoft 365 that want AI in Teams now, with DATEV and § 203 StGB, without a setup project. Everything about the edition is on the amaiko Kanzlei page, or book a demo straight away.

2. LUIGI AI: a box in the post and a DATEV mirror

LUIGI AI, from Bad Wurzach, is the other AI built only for tax firms.

Its model has a catch: LUIGI’s security page names a sub-processor whose listed job is mirroring DATEV holdings into LUIGI’s databases, and LUIGI’s own blog argues that a pure live connection “kann das nicht leisten”. Add a Kanzlei-Box that arrives at your office by post, and a three-part price: firm packages at €300, €600 and €1,000 a month as guide values, plus a DATEV add-on from €250 a month, plus a one-time activation from €500. LUIGI is its own web app, with no Teams integration.

Full comparison: amaiko vs LUIGI AI.

3. Langdock: an AI platform you assemble yourself

Berlin-based Langdock is not tax-firm software. It is a model-agnostic AI platform hosted in Germany and the EU, at €25 to €99 per user per month. It reaches DATEV through its MCP directory: Klardaten’s MCP server requires a Klardaten account with a DATEV connection and the MCP add-on.

The limits: you assemble the tax-firm solution yourself, from platform, connector and prompts, with two vendors in the data flow. And Langdock is a separate app with no Teams presence.

Full comparison: amaiko vs Langdock.

4. Microsoft 365 Copilot: in Teams, but no DATEV

Copilot sits in Word, Excel, Outlook and Teams. For a tax firm, two things are missing. First, DATEV: Copilot has no connection of its own, so access takes a third-party connector or custom work in Copilot Studio. Second, a clear answer on data location: through “flex routing”, Microsoft can allow AI processing outside the EU. It is on by default for EU tenants created after March 25, 2026; existing tenants have to check Message Center notice MC1269223 and opt out. On price, Copilot adds $30 per user per month on top of the Microsoft 365 licence.

Full comparison: amaiko vs Microsoft 365 Copilot.

5. nele.ai: chat without system connections

nele.ai, built by GAL Digital GmbH in Hesse, is multi-model chat on servers in Germany, with optional automatic pseudonymization of inputs “as far as apparent” and licensing by consumption packages.

The limits: nele.ai names no DATEV connection on its site, runs as its own web and desktop app with no Teams presence, and builds no memory. For work on client data, it remains a chat window next to DATEV.

Full comparison: amaiko vs nele.ai.

How to choose

• Your firm runs on Microsoft 365 and the AI should work in Teams today, with DATEV and Haufe included, § 203 StGB and no setup fee: amaiko Kanzlei, at €29.91 per user per month billed annually.
• You accept a DATEV mirror and a box in the office: LUIGI AI.
• You want an open platform and will build the DATEV connection with Klardaten yourself: Langdock.
• You do not need DATEV inside the AI and have flex routing under control: Microsoft 365 Copilot.
• Secure chat without system connections is enough: nele.ai.

For most tax firms on Microsoft 365, the answer is the first line. See for yourself in a demo.