Compare · Blue J
Blue J alternatives for UK accountants
Blue J is an AI tax research platform, founded in Toronto in 2015, with cited answers on UK, US and Canadian tax. It says more than 6,000 firms use it. If you’re weighing an alternative, compare where you can use it, how you pay, how security is evidenced and what answers draw on. Here’s how Nylon and five other options compare, and when Blue J is still the better fit.
Nylon vs Blue J: the short answer
As at 22 October 2026, in pounds sterling. Details and sources below.
Blue J
Nylon
Works in
Blue J’s web app; Legora in early access
Nylon, plus Claude, ChatGPT and Copilot (Adviser and Elite)
Contract
Annual, renews automatically; fees non-refundable
Monthly, cancel anytime
Price
£1,500 a year per user; VAT not stated
£39–£199 per user a month, ex VAT
Security
SOC 2 Type 2; ISO not described on its website
SOC 2 Type 1, SOC 2 Type 2, ISO 27001, ISO 42001
Jurisdictions
UK, US and Canada, depending on subscription
UK, Australia and New Zealand in one library
Choose Nylon for cited UK tax research, billed monthly, inside Claude, ChatGPT and Copilot, with ISO 27001 and ISO 42001 certified security. Choose Blue J if you also research US or Canadian tax, or want Tax Notes and IBFD commentary in your answers.
Each vendor’s own website is the source for its column.
The best Blue J alternatives at a glance
What each product says about itself on its own website, as at 22 October 2026. Prices exclude VAT unless stated.
Nylon
Cited AI answers from UK primary sources, in Nylon or your AI assistant
Yes, on every plan
£39, £99 or £199 per user a month
Tolley
Tolley commentary, practical guidance and HMRC manuals, with AI workflows
Yes, in Tolley+ with Protégé
Quote-based
Croner-i
Croner commentary and guidance, with a tax and VAT advice line
Yes, from Croner’s own content
Quote-based
Accordance
Multi-agent AI for tax, audit and accounting teams
Yes, with a source list
Not published
Lexis+ with Protégé
Broad UK legal research and drafting, with citation checks
Yes
Quote-based
ChatGPT or Claude on their own
Quick drafting where nobody needs to trace the source
Only with web search on
Free and paid plans
Why UK accountants choose Nylon over Blue J
Blue J is strong on cited research across UK, US and Canadian tax, with Tax Notes and IBFD commentary. Nylon is built for cited UK tax answers wherever you work, billed monthly.
Research inside your AI assistant
Adviser and Elite seats bring Nylon into Microsoft Copilot, Claude and ChatGPT, with every answer cited. Blue J announced a connector for Legora, the legal AI platform, on 19 October 2026: early access for selected joint customers, with general availability planned for November. A connector for Copilot, Claude or ChatGPT isn’t described on Blue J’s public pages.
Monthly, not annual
Nylon is billed monthly and you can cancel anytime. Blue J sells annual subscriptions that renew automatically unless you give written notice at least 14 days before the term ends. Its fees are non-refundable; if you cancel, you keep access until the term ends.
Per-user prices, published
Nylon publishes a per-user monthly price for Starter, Adviser and Elite, from £39 (ex VAT). Blue J’s UK site lists £1,500 a year per user for sole practitioners; firms buying for several users need a quote.
Independently certified
Nylon is SOC 2 Type I and Type II audited, and ISO 27001 and ISO 42001 certified. Blue J holds a SOC 2 Type 2 report, shared under NDA; ISO certification isn’t described on its website.
1. Nylon
Nylon: cited AI answers from UK primary sources
Nylon answers UK tax questions from tax legislation, HMRC manuals and guidance, and tribunal and court decisions, and links every citation to the source.
Cited answers
Every answer comes with hyperlinked citations to the primary source.
UK tax library
UK tax legislation, HMRC manuals and guidance, and tax decisions from the tribunals and courts.
Drafting and review
Draft advice letters, research memos and tax opinions, or upload client documents and ask what matters.
In your AI tools
Adviser and Elite seats include Nylon’s AI connector for Claude, ChatGPT and Microsoft Copilot.
Pricing
Starter £39, Adviser £99 and Elite £199 per user per month, ex VAT. Billed monthly; cancel anytime. Free 7-day trial. Enterprise pricing on request.
Nylon
When does a business have to register for VAT?
You must register if your taxable turnover for the last 12 months has gone over £90,000, or you expect it to go over £90,000 in the next 30 days alone [1]. Under the 12-month test, tell HMRC within 30 days of the end of the month you went over [2].
1
Value Added Tax Act 1994, Sch 1 para 1
2
Value Added Tax Act 1994, Sch 1 para 5
Illustrative example
Benchmark · October 2026
4.68 / 5
Nylon’s composite score on 91 CPA Program Australia Taxation questions, each graded blind against an expert reference answer.
Nylon
4.68
Claude Fable 5.1
4.32
GPT-6 Astra
4.28
Australian tax, compared with five general AI models. Specialist tools, including Blue J, weren’t tested.
Nylon vs Blue J, side by side
As at 22 October 2026. The Blue J column comes from Blue J’s website and help centre.
Where you use it
The Blue J web app. Since 19 October 2026, Blue J also works inside Legora through an MCP connector, in early access for selected customers of both, with general availability planned for November; you need both subscriptions. Connectors for Claude, ChatGPT or Microsoft Copilot aren’t described on Blue J’s public pages.
Nylon on the web, and Claude, ChatGPT and Microsoft Copilot through the AI connector (Adviser and Elite).
Contract
Annual subscriptions that renew automatically unless you give written notice at least 14 days before the term ends. Fees are non-refundable; if you cancel, you keep access until the term ends. Users can be changed only at the start of a term.
Monthly. Cancel anytime.
Price
Sole practitioners: £1,500 a year per user; Blue J doesn’t say whether that includes VAT. Teams: quote, adding a customer success manager, onboarding, usage insights and SSO.
£39, £99 or £199 per user a month, ex VAT. Enterprise: quote.
AI answers
Answers cite sources inline, and you can open each source in Blue J. Blue J says it retrieves only from its vetted library, “never the open web”, using models from OpenAI and Google. Usage is unlimited, including memo and email drafting.
Fast and research modes on every plan, plus deep research on Adviser and Elite. Every answer links each citation to the primary source.
What answers draw on
For the UK: Acts and statutory instruments, including Scottish, Welsh and Northern Ireland legislation; HMRC manuals and guidance; VAT notices; UK tax treaties; and decisions from the tax tribunals up to the Supreme Court. Updated daily, Blue J says.
Nylon’s library: UK tax legislation, HMRC manuals and guidance, and tax decisions from the tribunals and courts.
Jurisdictions
The UK, the US (federal and state) and Canada, with IBFD content for cross-border work. Which jurisdictions you get depends on your subscription; the UK plan lists the UK tax database.
UK, Australian and New Zealand tax legislation and guidance in one library.
Expert commentary
Tax Notes commentary, IBFD international tax content and curated web commentary from publications, law firms and accounting firms. Reading Tax Notes articles in full needs a separate Tax Notes subscription.
No editorial commentary. Nylon answers from the primary sources.
Drafting
Memos, client emails and checklists from your research, exported to Word or PDF. Uploaded files are deleted after 24 hours. Blue J’s agentic Workflows are in limited availability on its US database only.
Nylon drafts advice letters, research memos and tax opinions, and reviews uploaded client documents.
Security and data
A SOC 2 Type 2 report, audited annually and shared under NDA. ISO certification isn’t described on Blue J’s website. Customer data isn’t used to train AI models.
Nylon is SOC 2 Type I and Type II audited, and ISO 27001 and ISO 42001 certified. All data that passes through Nylon is encrypted in transit and at rest.
Trial
A 7-day free trial with no credit card. Team trials through sales.
Free 7-day trial when you sign up, or book a demo.
What you gain with Nylon
Nylon inside Microsoft Copilot, Claude and ChatGPT (Adviser and Elite)
Monthly billing: cancel anytime, with no annual renewal
A published per-user monthly price for every plan
SOC 2 Type I and Type II audited, and ISO 27001 and ISO 42001 certified
What you give up
US federal and state, and Canadian, tax research in the same tool
Tax Notes and IBFD commentary inside your answers
Blue J inside Legora, if your firm uses it (general availability planned for November)
Test Nylon on your own Blue J questions
Bring three UK tax questions you researched in Blue J this month. In the demo, we’ll answer them in Nylon with every source linked.
Other Blue J alternatives
Each summary comes from the product’s own website, as at 22 October 2026.
2
Tolley
LexisNexis’s UK tax research and guidance. Tolley+ with Protégé, formerly Tolley+ AI, gives citation-backed AI answers, drafting and guided workflows grounded in Tolley content, including Simon’s and De Voil, HMRC manuals and practical guidance.
Best for
Firms whose work runs on Tolley commentary, practical guidance and tax tools.
Pricing
Quote-based.
Consider it if
You want editor-written commentary and practical guidance alongside AI answers.
3
Croner-i
Croner’s tax, audit and accounting information service: commentary, HMRC manuals, legislation and cases, CPD and a tax and VAT advice line. Its AI assistant, Croner Intelligence, answers only from Croner’s own expert content.
Best for
Firms that want Croner commentary and guidance, with an expert advice line.
Pricing
Quote-based.
Consider it if
You want a telephone advice line alongside your research tool.
4
Accordance
A San Francisco multi-agent AI platform for tax, audit and accounting teams, founded in 2024 by former Stanford AI researchers. It shows its reasoning and a source list.
Best for
Firms that want one AI across tax, audit and accounting work.
Pricing
Not published; book a demo.
Consider it if
You want agentic AI across your practice. UK tax coverage isn’t described on Accordance’s public pages.
5
Lexis+ with Protégé
LexisNexis’s legal AI for drafting, research and analysis, formerly Lexis+ AI. It grounds work in LexisNexis case law, legislation and secondary sources, checks citations with case signals, and connects to iManage, SharePoint and NetDocuments.
Best for
Law firms and legal teams doing broad legal research and drafting.
Pricing
Quote-based.
Consider it if
Your work is mostly legal rather than tax. For tax, LexisNexis sells Tolley+ with Protégé.
6
ChatGPT or Claude on their own
General AI assistants that answer from their training data and, when it’s on, web search. OpenAI’s help centre warns that ChatGPT’s citations can be incomplete, outdated or incorrect.
Best for
Quick drafting and orientation where nobody needs to trace the answer.
Pricing
Free and paid plans.
Consider it if
You add Nylon’s AI connector, so they search Nylon’s library and cite the source.
Which should you choose?
Match the tool to the work you do most.
If you want cited UK tax answers in your AI tools
Nylon
Monthly per-user plans, in Nylon or in Copilot, Claude and ChatGPT.
If you also research US or Canadian tax
Blue J
UK, US and Canadian tax in one tool, with Tax Notes and IBFD content.
If your work runs on Tolley’s guidance
Tolley
Simon’s, De Voil, practical guidance and AI workflows.
If you want an expert advice line
Croner-i
Croner commentary and guidance, with a tax and VAT advice line.
If you want AI across tax, audit and accounting
Accordance
Multi-agent AI with visible reasoning and a source list.
If your work is mostly legal
Lexis+ with Protégé
Broad UK legal research and drafting.
Security your firm can check
Nylon is SOC 2 Type I and Type II audited, and ISO 27001 and ISO 42001 certified.
Independently audited
SOC 2 Type I and Type II reports are available, and Nylon holds ISO 27001 and ISO 42001 certification.
Encrypted
All data that passes through Nylon is encrypted in transit and at rest.
Not used for training
Your questions and Nylon’s answers aren’t shared, and your inputs are never used to train AI models.
Admin controls
Every plan includes advanced organisational controls.
Baqir Hussein, FCCA · Founder & Director, Finex Chartered Certified Accountants
Blue J alternatives: frequently asked questions
Questions about switching? Book a demo or email support@usenylon.com.
What is the best alternative to Blue J?
If you want cited AI answers on UK tax, billed monthly and available inside Copilot, Claude and ChatGPT (Adviser and Elite), Nylon: it links every answer to the primary source and is ISO 27001 and ISO 42001 certified. If your work runs on commentary and practical guidance, Tolley or Croner-i. For AI across tax, audit and accounting, Accordance. For broad legal research, Lexis+ with Protégé.
How does Blue J work?
As at 22 October 2026, Blue J says it answers tax questions from a curated library of primary sources and commentary, never the open web, and cites its sources inline. For the UK, that library includes legislation, HMRC manuals and guidance, VAT notices, tax treaties, and tribunal and court decisions, plus Tax Notes commentary and IBFD content. Blue J uses models from OpenAI and Google, and says customer data isn’t used to train them.
How does Blue J pricing compare with Nylon?
As at 22 October 2026, Blue J’s UK site lists £1,500 a year per user for sole practitioners, as an annual subscription; it doesn’t say whether that includes VAT. Teams need a quote. Nylon costs £39, £99 or £199 per user a month, ex VAT, billed monthly. Over a year, Nylon Starter and Adviser cost less than £1,500 per user, and Elite costs more.
Does Nylon cover US or Canadian tax?
No. Nylon’s library covers UK, Australian and New Zealand tax legislation and guidance. Blue J covers the UK, the US and Canada, depending on your subscription, so it may suit firms with US or Canadian clients better.
Can I use Nylon alongside Blue J?
Yes. Nylon is billed monthly, so you can run both and compare them on your own questions.
Does Nylon have a free trial?
Yes. Start a free 7-day trial when you sign up, or book a demo to see Nylon on your own questions. Plans are monthly and you can cancel anytime. Blue J offers a 7-day free trial with no credit card required.
Can I use Nylon in ChatGPT, Claude or Copilot?
Yes, with an Adviser or Elite seat. Nylon’s AI connector lets those assistants search Nylon’s library and cite the source.
Is Nylon secure enough for client work?
Nylon is SOC 2 Type I and Type II audited, and ISO 27001 and ISO 42001 certified. Data is encrypted in transit and at rest, and your inputs are never used to train AI models.
Keep exploring
Nylon for accountants
Research, drafting and review for accounting firms.
Tax research benchmark
91 Australian tax questions, six systems, graded blind.
AI connectors
Nylon in Claude, ChatGPT and Copilot.
Plans
Starter, Adviser and Elite, billed monthly.
Information about other products comes from their own websites as at 22 October 2026 and can change. Prices are in pounds sterling. Blue J is a trade mark of Blue J Legal Inc. Other product names belong to their owners. Nylon isn’t affiliated with or endorsed by any of them. Nylon’s October 2026 benchmark compared general AI models, not the other products on this page. Spotted something out of date? Email support@usenylon.com.