Practitioner training manual · Version 1.0 · 29 July 2026
ChatGPT is OpenAI's assistant, and the most widely used AI tool in the world. For a finance professional the important thing to understand on day one is that "ChatGPT" is not one model. Several sit behind the same box, they differ enormously in quality, and the cheap ones are the default.
A fast model answers instantly and is fine for tidying a paragraph. A reasoning model thinks before it replies and is the only sensible choice for a technical accounting question. Picking the wrong one is the single most common reason people conclude that AI is not useful for professional work.
| What you see in the picker | Use it for | Available on |
|---|---|---|
| GPT-5.5 Instant | The fast everyday default. Formatting, rewriting, quick questions, tidying a list. | Every plan, including Free |
| GPT-5.6 Sol | The flagship. Technical accounting positions, long document review, anything where being wrong costs you. | Plus and above |
| GPT-5.6 Sol Pro | The highest-effort reasoning setting for the hardest problems. | Pro and Enterprise |
| GPT-5.6 Terra and Luna | Balanced and lightweight members of the same family, used for volume work. | Plus and above in chat; Free and Go see Terra only inside Work and Codex on desktop |
| GPT-5 Thinking Mini | Light reasoning when Instant is too shallow but you do not need the flagship. | Every plan |
Twenty minutes of setup, most of it in two settings screens that almost nobody opens.
Most comparisons focus on price and message limits. For our work the deciding number is how much text the model can actually take in at once, because that is what determines whether it can read a full annual report or only a third of it.
| Plan | Reported price | What you get | Input it can take at once |
|---|---|---|---|
| Free | $0 | Limited access to the fast model, limited messages, uploads, data analysis, deep research and memory. Cannot create custom GPTs. | About 12 pages on the fast model |
| Go | About $8/mo | More messages, uploads and memory, scheduled tasks, ability to create GPTs. May include ads. Does not reach the flagship model in normal chat. | About 40 pages fast, about 320 pages reasoning |
| Plus | About $20/mo | The flagship reasoning models, expanded deep research, projects, scheduled tasks, custom GPTs, record mode, interactive tables and charts, and the Excel, PowerPoint and Google Sheets extensions. The default recommendation for a practitioner. | About 40 pages fast, about 320 pages reasoning |
| Pro | From about $100/mo, or about $200/mo | Everything in Plus with 5x or 20x the usage, the Pro reasoning tier, maximum deep research, and the largest context of any individual plan. | About 250 pages fast, about 680 pages reasoning |
| Business | $20/seat/mo billed annually, $25 monthly, minimum 2 seats | Shared workspace and shared projects, admin console, SAML SSO, 60 plus connected apps including Drive and SharePoint, company knowledge, workspace GPTs, SOC 2 Type 2, and no training on your data. | Larger reasoning context than individual plans |
| Enterprise | Custom | Expanded context, SCIM, enterprise key management, role-based access, IP allowlisting, compliance logs, data residency in ten regions, and no training on your business data by default. | The largest available |
These are annotated drawings rather than captured screenshots, so each control can be numbered and explained. Menu wording shifts between releases; the positions and the ideas are stable.
In Settings, open personalisation and custom instructions. There are two boxes: what ChatGPT should know about you, and how it should respond. This travels with every new chat and is the highest-return five minutes in this manual.
I am a practising Chartered Accountant in Dhaka, Bangladesh, with 12 years of banking experience. My work covers statutory audit, IFRS reporting, income tax and VAT under Bangladeshi law, and bank regulatory reporting. I work in BDT. My outputs go into audit files, tax returns, client reports and board papers, so accuracy matters more than speed and everything I use gets reviewed.
- Professional but conversational. No marketing language, no filler, no restating my question back to me. - Lead with the answer, then the reasoning. Short paragraphs. - British spelling. Amounts in BDT with thousands separators. - Cite the standard or section you rely on (IFRS, IAS, ISA, ITA 2023, VAT and SD Act 2012, Bangladesh Bank circular). If you are not certain a provision is current, say so explicitly rather than guessing. - Whenever a calculation is involved, run it with the analysis tool and show the code. Never do arithmetic in prose. - Tell me when my premise looks wrong. Do not agree by default. - If a question needs the reasoning model to answer properly, say so before you answer.
In Settings, under data controls, find the option covering whether your content is used to improve the models. On Free, Go, Plus and Pro this is on by default with an opt-out available. On Business and Enterprise, OpenAI states that your content is not used for training. Make the decision deliberately, record it, and re-check it after major product updates.
A prompt is an instruction to a capable assistant who cannot see your screen, does not know your client, and will fill any gap you leave with an assumption.
| Part | What it does | Example |
|---|---|---|
| Role | Sets the standard of the answer. | "You are an audit manager reviewing a first-year engagement." |
| Context | Facts it cannot know. | "Dhaka garments exporter, turnover BDT 4.2 billion, June year end, first year under IFRS 16." |
| Task | The single thing you want done. | "Draft the lease liability disclosure note." |
| Constraints | The rules and limits. | "Comply with IFRS 16. Do not invent figures. Flag what you need from me." |
| Format | The shape of the output. | "A maturity table, then three paragraphs, under 400 words." |
Weak: "Explain deferred tax."
You get a textbook page you already know.
Strong: "You are advising the CFO of a Bangladeshi manufacturer. Accounting depreciation is straight line over ten years, tax depreciation is reducing balance at 20 percent, the asset cost BDT 50,000,000 and was acquired on 1 July 2025. Compute the deferred tax liability at 30 June 2026 at a 27.5 percent rate using the analysis tool, show the temporary difference workings in a table, then write three sentences explaining the movement for the board pack."
You get a schedule you can check and narrative you can lift.
Before I use this, review your own output as a sceptical engagement partner would. List, in order of severity: 1. Any figure you calculated in prose rather than computed with the analysis tool, or took from something other than my source data. 2. Any statement of law or standard you are less than fully confident is current, with what I should verify and where. 3. Any assumption you made that I did not give you. 4. Anything a reviewer would send back. Do not rewrite the draft yet. Just give me the list.
This is where ChatGPT stops being a chat toy for an accountant. Attach a spreadsheet, tell it to analyse, and it writes and runs real Python on your data.
A language model predicting the next word is not a calculator. When the analysis tool runs, actual code executes and the arithmetic is real. Two ways to trigger it:
Asking to see the code is not about reading Python. It is about checking which rate was applied, how the days were counted, and whether the closing balance ties.
It returns Excel files, Word documents, PowerPoint decks, charts, and interactive tables you can sort in the chat. Ask for the format you want.
Attached is a two-year trial balance for [client], [industry], year ended [date]. Materiality is BDT [amount]. Use the analysis tool so the arithmetic is computed rather than estimated, and show me the code. 1. Build a variance table: account, prior year, current year, movement in BDT and percent. Sort by absolute movement. 2. Flag every account where the movement exceeds materiality OR exceeds 25 percent, whichever captures more. 3. For each flagged account, give the two most likely legitimate business explanations and the two most likely misstatement risks, with the relevant assertion. 4. List accounts that moved suspiciously little, which can indicate a rolled forward balance nobody reconciled. 5. Identify apparent classification errors between current and non-current, or between cost of sales and operating expenses. Do not conclude on any item. Give me a review agenda, not an opinion. Return the variance table as an Excel file.
Canvas opens a document beside the chat that you and ChatGPT edit together, rather than regenerating the whole reply each time. Use it for anything you will iterate on: a memorandum, a report section, a policy note. You can edit directly, highlight a paragraph and ask for a change to that part only, and keep the rest untouched.
Attached is a [lease / facility / service] agreement. Use the reasoning model. Extract into a table, with the clause number beside each item: - Parties, commencement, term, renewal and termination options - All payment obligations, amounts, escalation clauses and payment dates - Any variable consideration or contingent payment - Security, guarantees and covenants, including financial covenants with their defined ratios - Change of control, penalty and default provisions Then, separately: which clauses drive the treatment under IFRS 16 and IFRS 9, and what figures I would need to extract to build the schedule. Quote nothing longer than a phrase. Give clause references so I can verify every line myself.
Twelve places where this pays for itself in the first month. Each is a prompt pattern to adapt, not a magic button.
Turn this raw finding into a management letter point in condition, criteria, cause, effect, recommendation format. Raw finding: [what you found, including sample size, exceptions, amounts and the period] Rules: - Criteria must cite the specific control objective or standard, not a vague reference to "best practice". - Quantify the effect in BDT where my facts allow it, and write "not quantified" where they do not. Do not invent a number. - The recommendation must be specific enough for the client to implement without asking us what we meant. - Rate it high, medium or low and justify the rating in one sentence. - Neutral professional tone, no blame language, under 220 words.
The highest value and highest risk area in this manual. The value is in structure, computation and drafting. The risk is in statutory recall.
Use the reasoning model. I have attached [the relevant sections / the SRO / the circular]. Work only from the attached text. If something needed for the answer is not in the attachment, say "not covered in the provided text" and tell me exactly what else to give you. Do not fill gaps from your general knowledge of tax law. Facts: [the transaction, amounts, dates and parties] Questions: 1. Which provision in the attached text applies, by section and sub-section reference only? 2. What is the resulting treatment, computed step by step with the analysis tool? 3. What is the strongest argument the tax authority could make against this position? 4. What documentation should be on file to support it?
Attached is a circular issued by [regulator] dated [date]. Produce a one-page impact note for our [finance / credit risk / compliance] committee: 1. What changed, in plain language, but only where the circular itself states the previous position. Where it does not, say so. 2. Effective date and any transitional relief, quoted by paragraph. 3. Which functions are affected and what each must do differently. 4. What our systems and reports must capture that they may not capture today. 5. A compliance checklist of no more than eight items, each one testable. 6. Open questions to raise with the regulator or our lawyers. Work only from the attached circular. Do not rely on your own knowledge of prior circulars. List anything you need under "documents to obtain".
Everything so far has been one conversation at a time. This part is about making ChatGPT carry context so you stop re-explaining yourself, and about making a whole team produce consistent output.
A Project holds files and standing instructions, and every chat started inside it inherits both. Available across plans, with shared projects on Business and Enterprise.
A custom GPT is a saved assistant with fixed instructions and attached reference files. Build it once, use it forever, share it with the team. This is the feature that turns individual productivity into firm capability, and it is the one most firms never get to.
Four worth building in your first month:
You are a Bangladesh tax reference assistant for a chartered accountancy practice. You answer only from the files attached to this GPT. Rules you never break: 1. Every substantive answer cites the section, sub-section, SRO number or paragraph in the attached files. No citation, no answer. 2. If the attached files do not cover the question, say "not covered in the loaded sources" and list what should be uploaded. Never answer from general knowledge of tax law, including law from other countries. 3. Never state a rate, threshold or due date that is not in the files. 4. Compute with the analysis tool and show workings. Never do arithmetic in prose. 5. Where the files contain provisions from different years, say which year you are applying and warn me to confirm it against the operative Finance Act. 6. End every answer with: "Verify against the current text before use."
The gap between an average user and a strong one is almost entirely this: strong users make the machine compute, and they automate anything they do twice.
Deep research runs a longer multi-source investigation and returns a report with citations. It genuinely helps with market and industry work, regulatory landscape reviews, and comparator analysis. It does not replace reading the primary source on a technical accounting or tax question, and every citation still needs opening.
Research question: [state it in one sentence] Scope: - Jurisdiction: [Bangladesh / regional / global], period: [dates] - Include: [regulator publications, listed company financial statements, industry association data] - Exclude: vendor marketing, undated blog posts, aggregator sites Deliverable: 1. Findings, each one attributed to a source I can open 2. Where sources disagree, show the disagreement rather than resolving it 3. A table of the quantitative data points with source and date beside each 4. What you could not find, stated explicitly rather than filled in 5. The three questions this research raises that I should investigate next Do not estimate any figure. If a number is not in a source, mark it as "not found".
On Plus and above, ChatGPT works inside Excel, PowerPoint and Google Sheets. For someone who lives in a spreadsheet, this is the highest-impact single feature in the product: it reads the live workbook, traces where a number comes from, explains a formula chain, builds schedules and fixes broken references. Review every change before accepting it, exactly as you would review a junior's edit.
A subscription covers you using ChatGPT. The API is for building the model into something else, and is billed per token, entirely separately. A token is roughly three quarters of an English word.
| Model | Input, per million tokens | Output, per million tokens |
|---|---|---|
| GPT-5.6 Sol | $5.00 | $30.00 |
| GPT-5.6 Terra | $2.50 | $15.00 |
| GPT-5.6 Luna | $1.00 | $6.00 |
Computed, not estimated. Assumptions stated so you can re-run them with your own volumes.
| Scenario | Assumption | Monthly cost |
|---|---|---|
| 40 client review memos | 15,000 input and 3,000 output tokens each, Terra | $3.30 |
| Same, on the flagship | Identical volumes, Sol | $6.60 |
| 200 circulars summarised | 8,000 input and 1,500 output each, Luna, run as a batch | $1.70 |
| One 150,000-token annual report read | Single call with 5,000 tokens of output, Terra | $0.45 |
A Chartered Accountant's duty of confidentiality has no exception for convenient software. With ChatGPT this section carries extra weight, because on individual plans the training default runs against you.
For most analytical work you do not need identifying data. Replace the client name with "the Company", strip the TIN, BIN and account numbers, keep the figures. The analysis is identical and the exposure is far lower.
Copy, paste, replace the bracketed parts. Type in the box to filter.
Attached: the bank statement and the cash book for [period]. Use the analysis tool and show the code. 1. Match transactions by amount and date, allowing a tolerance of [n] days. 2. List unmatched bank items and unmatched book items separately. 3. Build the reconciliation statement from book balance to bank balance. 4. Flag anything unusual: round sums, transactions on non-working days, payments to one party split just below [approval threshold], reversals. The reconciliation must tie exactly. If it does not tie, tell me the difference rather than forcing it. Return the working as an Excel file.
Use the reasoning model. Attached: our loan portfolio extract and our staging policy document. Working only from my attached policy, and computing with the analysis tool: 1. Apply the staging criteria to each exposure and produce a stage summary by count and by exposure amount. 2. Identify exposures where the policy is ambiguous or two criteria conflict, and list them for manual judgement. 3. Recompute ECL using the PD, LGD and EAD I supplied. Do not supply your own risk parameters under any circumstances. 4. Reconcile your total to our reported provision and explain each difference. 5. Draft the model documentation section describing the staging methodology, suitable for our audit file and regulatory review.
Attached: monthly sales per the general ledger and the VAT returns filed for the same period. Using the analysis tool, build a reconciliation from accounting turnover to declared taxable turnover, month by month, showing each reconciling item separately: exports and zero rated supplies, exempt supplies, non-taxable income, timing differences on advances, credit notes, related party transfers, and anything else the data supports. For each unexplained difference, list the three most likely causes ranked by how often they occur in practice, and the document I should request to resolve it. Do not tell me the VAT treatment of anything unless I have given you the provision.
Use the reasoning model. Attached: an assessment order for [taxpayer], assessment year [year]. Produce a table with one row per addition or disallowance, columns: paragraph reference, description, amount, the reason the officer gave, and the evidence the order says was considered. Then, separately: - Which additions rest on a factual finding we could rebut with documents, and what documents would be needed. - Which rest on an interpretation of law, quoted from the order itself. - The order in which grounds of appeal should be argued, strongest first, with one sentence on why. Work only from the attached order. Do not assess the merits under any provision I have not given you.
Attached: management accounts for [period] with budget and prior year comparatives. Write the finance commentary for the board pack: - Open with the three things the board must know, under 80 words total. - Then revenue, margin, cost and cash, one short paragraph each, each anchored to a specific figure from the attachment. - Explain variances only where the data supports an explanation. Where it does not, write "driver not identifiable from the data provided". - Close with the decisions the board is being asked to make. Plain language, no adjectives that are not doing work, under 600 words.
Use the reasoning model. Facts: [the transaction in full, with dates, amounts and contract terms] Part 1: The accounting treatment under [standard], with the paragraph references you rely on. Flag any reference you are not fully confident about and tell me to verify it. Part 2: Now act as the reviewing partner who disagrees. Write the strongest argument for a different treatment. Part 3: What additional facts or documents would settle the question, and what the disclosure would need to say under each treatment. Do not reconcile the two positions. I want the disagreement visible.
Attached workbook. Before changing anything: 1. Map the calculation chain: which sheet feeds which, and where the inputs actually live. 2. List every hard-coded number sitting inside a formula, with its cell reference. These are the errors waiting to happen. 3. List broken references, inconsistent formulas within a row or column, and any circular logic. 4. Tell me which three fixes carry the highest risk of changing a reported figure, so I can check those myself first. Then wait for my instruction before you edit anything.
Attached: the full year journal listing. Use the analysis tool and show the code for every test. Run and report separately: 1. Entries posted after the period end date but dated within the period. 2. Round-sum entries above BDT [threshold]. 3. Entries posted by users who post fewer than [n] entries a year. 4. Entries posted outside working hours or on public holidays. 5. Account pairings that occur fewer than [n] times in the year. 6. Entries just below BDT [approval threshold]. For each population give the count, the total value, and the ten largest items. Do not conclude on any entry. This is a selection basis, not a finding.
Rewrite the attached technical note for [the managing director / the audit committee chair / a family shareholder], who is intelligent but not an accountant. Rules: - Lead with what it means for them: the cash effect, the reported profit effect, and the decision they need to make. - No standard numbers or section references in the body. Footnote them. - No jargon without a plain definition on first use. - Keep every figure exactly as it appears in the source. Change no number. - Under 350 words, ending with the one question I need them to answer.
This prompt gave me a weak answer: "[paste your prompt]" The answer was weak because: [too generic / wrong format / invented figures / missed the point / used the fast model when it needed reasoning]. Rewrite the prompt so it works. Show me the improved version, then explain in three bullets what you changed and why, so I can apply the same thinking myself next time.
No prompt matches that word. Clear the filter to see all of them.
Thirty minutes a day on real work, not practice work. Progress is held in the page only, so it resets if you reload.
Bangladeshi statutory references in this manual are illustrative. Always work from the current text of the Income Tax Act 2023, the Value Added Tax and Supplementary Duty Act 2012, the operative Finance Act, applicable SROs, and current Bangladesh Bank circulars.
| Term | What it means in practice |
|---|---|
| Prompt | The instruction you give. Output quality tracks prompt quality more than anything else. |
| Context window | How much text the model holds at once. The reason a plan matters for reading long reports. |
| Token | The billing unit for API use. Roughly three quarters of an English word. |
| Hallucination | Confident, fluent output that is factually wrong. The core professional risk. |
| Reasoning model | A model that thinks before answering. Slower, far better on judgement. |
| Analysis tool | Code execution on your uploaded data. What turns estimated arithmetic into computed arithmetic. |
| Canvas | A side-by-side document you and the model edit together instead of regenerating. |
| Custom GPT | A saved assistant with fixed instructions and files, shareable with your team. |
| Project | A workspace holding files and instructions shared by every chat inside it. |
| Deep research | A long multi-source investigation returning a report with citations. |
| Connector or app | A link to another system, such as Drive or SharePoint, that the model can read. |
