A chief accountant at a small trading company received an invoice for $1,300 for consulting services. She paid it, received the acceptance certificate, and closed the month. Six months later, the tax authority disallowed the expenses under that certificate: it lacked mandatory details — the contractor's tax identification number and a reference to the contract. Penalty, interest, additional tax. Sound familiar? If you've encountered something like this, you understand: accounting is not just "numbers in the accounting software" but a strict system of rules where every journal entry rests on law and accounting standards.
In this article, I'll walk through one typical scenario — from the source document to the financial statements — and show how the Accounting Law and the accounting standards work in practice. You'll see where mistakes most often occur and how to avoid them. And at the end — how to master this profession if you're just starting out.
Why accounting is not just "numbers" but a system of rules
Accounting is governed by the Accounting Law. It sets out general requirements: who must keep records, which documents are needed, how to store information. The specific rules for recording transactions are laid down in the accounting standards (PBU). For example, PBU 1/2008 defines the accounting policy, PBU 4/99 — the financial statements, PBU 9/99 and 10/99 — income and expenses. More on the topic: Profession.
If an accountant doesn't know these rules, they act by guesswork. And then mistakes surface not immediately but during an audit or when preparing the financial statements, when it's too late to correct them. The mechanism is simple: every business transaction must be supported by a source document that contains mandatory details (Art. 9 of the Accounting Law). No details — no transaction for accounting. No transaction — no journal entry. No journal entry — the financial statements are unreliable. More on the topic: Tax Law in Practice.
A typical scenario: from source documents to financial statements
Let's imagine a company on the general tax system that provides services. In January 2026 it received materials from a supplier worth $1,300, including $200 of VAT. Payment was made in February. How will the accountant record these transactions?
Step 1. Receipt of materials. Documents needed: a goods delivery note (or a universal transfer document) and an invoice. We check the details: supplier's name, tax identification number, registration number, date, amount, VAT. If everything is in order, we make the journal entries:
- Debit 10 Credit 60 — $1,100 (materials recorded without VAT)
- Debit 19 Credit 60 — $200 (input VAT recorded)
Step 2. Payment to the supplier. In February we transfer the money:
- Debit 60 Credit 51 — $1,300 (invoice paid)
Step 3. VAT deduction. On the basis of the invoice and the source documents, we claim the VAT for deduction:
- Debit 68/VAT Credit 19 — $200
Step 4. Preparing the financial statements. At the end of the quarter, the accountant prepares the VAT return, where the deduction is reflected, and the financial statements, where the materials are shown on account 10.
Now imagine that the delivery note lacked the supplier's tax identification number. What happens? During an audit, the tax authority will disallow the VAT deduction and the corporate income tax expenses. The company will pay an additional $200 of VAT, $220 of income tax (if the expenses are not accepted), plus interest and a penalty. And that's just for one transaction. What if there are dozens of such documents? More on the topic: Medical Expense Tax Deduction.
Where mistakes most often happen: three typical traps
Trap 1. Incorrect account correspondence. Novice accountants sometimes mix up accounts: for example, they record the purchase of materials directly to account 20 "Main production", bypassing account 10. As a result, the cost of goods and balances are distorted. An audit will show a mismatch between the accounting data and the financial statements.
Trap 2. Ignoring the accounting standards when forming the accounting policy. The accounting policy is not a formality. If it does not specify the depreciation method or the inventory valuation method, the accountant applies the first option that comes to mind. And then, during an audit, it turns out that it contradicts the accounting standards. For example, the inventory standard requires inventories to be valued on issue to production using one of the methods (FIFO, average cost, etc.). If the method is not fixed, the tax authority may recalculate the income tax.
Trap 3. Incorrect completion of source documents. As in the example with consulting services. Or the absence of the chief accountant's signature on a document, if this is provided for by the accounting policy. Under Art. 9 of the Accounting Law, a source document must be signed by the persons responsible for its completion. If there is no signature, the document is invalid.
To avoid these mistakes, you need not only to know the journal entries but also to understand the logic of the standards. One way to master the material is to take a specialized course that covers exactly such situations. For more on the profession and entry paths — see the article Profession.
How to learn accounting: three paths and their cost
You can master accounting in different ways. Here are three typical options.
1. On your own from textbooks and open sources. Plus: free. Minus: no feedback, it's easy to miss important details, and no one will check your journal entries for mistakes. Time: from several months to years, depending on intensity.
2. Professional development or retraining courses. Plus: a structured program, an instructor checks your assignments. Minus: the cost (from $150 to $500 and up), and the quality depends heavily on the school. Time: usually 2–6 months.
3. Practice under the guidance of an experienced accountant. Plus: real tasks, instant feedback. Minus: you need to find a mentor who agrees to teach, and it's often low-paid work. Time: from six months.
As you can see, each path has a trade-off. Self-study gives you freedom, but there's a high risk of gaps. Courses give you a system, but they cost money. Practice is the fastest way to gain skills, but it requires a mentor.
On the asibiont.com platform there is a course Accounting and Reporting that is built on real examples and includes sample documents: the accounting policy, registers, journal entries. It can be a good complement to practice or replace self-study if you want to save time and avoid typical mistakes.
Who this path suits and who it doesn't
Accounting is not for everyone. If you're not ready for monotonous work with documents, if you find it hard to focus on details, if you don't like everything having to be strictly by the rules — this profession is probably not for you. But if you enjoy bringing order to numbers, if you get pleasure from everything adding up, and if you're ready to keep learning (the laws change), then it's worth a try.
You can start small: try keeping the books for a small company or a sole proprietor, take a course, work as an accountant's assistant. The main thing is not to fear mistakes but to learn to correct them before they become a problem.
In closing, I want to say: accounting is the language in which business speaks to the state. And if you learn this language, you will become a valuable specialist whom no automation can replace. The course Accounting and Reporting will help you take the first steps in this direction — it covers journal entries, financial statements, the accounting policy, and tax accounting. Start small, but start.