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C9 AI — The AI workspace for CPAs

Financial work,
with the source
still attached.

Ask questions about tax slips, statements and records. Get answers grounded in your documents and shared reference Library, with the source still attached.

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Private beta — access is by invitation while we finish testing. Request access to get on the list.

Northstar Accounting

Built-in AI active

T4_EleanorPark_2025.pdfp. 1 / 1

T4 — Statement of Remuneration Paid

2025

Box 10 · Province

Box 14 · Employment income

84,230.00

Box 16 · CPP contributions

4,034.10

Box 18 · EI premiums

1,077.48

Box 22 · Income tax deducted

16,846.00

Box 24 · EI insurable earnings

65,700.00

Highlighted boxes are the exact passages cited in the answer.

Personal tax · Eleanor Park · 2025 · Canada

Review memo

What employment income and tax deducted does this slip show?

Answered from 1 document · 2 cited boxes

Employment income is $84,230.00 and income tax deducted is $16,846.00 — an effective withholding rate of 20.0%.

T4 — Box 14 · p. 1T4 — Box 22 · p. 1

Line	Amount	Source
10100	84,230.00	Box 14
43700	16,846.00	Box 22

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01CPAs & accounting firms

02Bookkeepers

03Payroll experts

04Individual filers

Shared reference Library

One place for the sources you return to.

Add guides, checklists, exported emails, screenshots and documents once. Save web pages from approved sources as a one-time snapshot. Every workspace chat can draw on the Library without pulling in another client’s files.

Library sources are identified in chat citations.

Only admins can approve additional web domains.

C9 AI / Library

Shared across workspaces

Library

Reference material for every workspace chat

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https://canada.ca/...Add

Trusted sourcesOfficial + admin approved

In your library (3)

Preview

2026 tax reference guide.pdf

18 pages · PDF

Document

Tax authority guidance

Saved web page · canada.ca

Web page

Year-end checklist.eml

2 pages · Email

C9 AI / Usage

73090

Credits used per day

119 fast · 33 deep research

Fast answers Deep researchYour own keys and local models are not counted

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Know exactly what you've used.

Settings > Usage charts your credits day by day, with fast answers and deep research in separate colours. Pick a 7, 30 or 90 day window and see the plan allowance, courtesy answers and top-up packs you have left.

Deep research answers use 3 credits, fast answers 1.

Top-up credits stay valid for 12 months from purchase.

One workspace. Every engagement.

Move from document to decision without losing the evidence.

Answers with sources

Every figure links back to the document and page it came from.

Start with a question

Open a new chat from the workspaces page and get straight to the work.

Tax research

Ask plain-language questions and follow the evidence behind the answer.

Client workspaces

Keep each engagement's documents and conversations separate.

Know what you've used

A daily chart shows credits spent, split between fast answers and deep research.

Firm controls

Admins manage models, stored keys, trusted sources and developer mode.

Pricing

Start free. Upgrade when the work demands it.

Fast answers cost 1 credit, deep research 3. Plan changes always ask you to confirm first, and unused plan credits carry over when you move up.

Free

3 fast inquiries to try it out
Client workspaces and Library
Answers with document citations
Your own API keys or a local model

Plus

$19 / month

500 credits every month
Fast answers cost 1 credit, deep research 3
100 extra courtesy fast answers
Top-up packs available, valid 12 months

Pro

Local / BYOK

Custom

Run local models on your own hardware
Bring your own Claude, OpenAI or Gemini keys
No c9 credits used — your provider bills you
Firm-wide model and key policies

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Need more credits this month? Top-ups are added on top of your plan and each pack stays valid for 12 months from purchase.

$10

200 credits

$15

350 credits

$20

500 credits

Good to know

Online checkout is being connected — request access and we'll set up your account and plan when purchases open.
Bring your own API keys or run a local model at no c9 credit cost.
Questions about firm-wide model policies? Write to hello@codeninesystems.com.

Designed for sensitive work

Your documents remain your documents.

Private storage, protected document text, separate client workspaces, short-lived file access, and a record of every upload, open, and delete.

Separate by client

Engagements never share documents or conversations.

Traceable by design

Answers cite the source; actions appear in the audit trail.

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Use built-in AI, your API keys, or a model running locally.

Bring clarity to the work behind every number.

Start a private workspace for your next client, return, reconciliation, or research question.

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Private beta — access is by invitation while we finish testing

Financial work,with the sourcestill attached.