Korea Computerized Tax Accounting Level 2 (전산세무 2급) common mistakes
Korea Computerized Tax Accounting Level 2 (전산세무 2급) · Understand the traps and how to avoid them.
Entering the transaction date in the input screen as the date of the tax invoice or the date of receipt instead of the actual transaction (거래) date, so the software posts the entry to the wrong reporting period and the VAT return and the ledger disagree.
Candidates treat the invoice issue date as the accounting date because it is the most visible date on the document, and the software's date field is pre-filled with the system date, so they overwrite it with whatever date they read first. In 전산세무 2급 the input screens separate 거래일자, 작성일자, and 입금일자, and mixing them shifts entries across quarters.
What to do instead
Before entering any entry, read the source document and identify the actual transaction date separately from the invoice date. Enter the 거래일자 field first, then verify with the 조회 (inquiry) screen that the entry falls in the intended taxable period. Build a habit of checking the period totals at the end of each input batch.
Failing to correct an entry properly - deleting or re-entering a transaction instead of using the software's 수정 (modify) function, which leaves duplicate entries or breaks the link to the source slip and produces a trial balance that does not match the journal.
Candidates panic when they spot an error after posting and either add a reversing entry in the wrong direction or delete the whole line and retype it, often with a different account code. They do not know that the modify function preserves the audit trail and that deletion in a closed period is blocked.
What to do instead
Learn the difference between 수정 (edit an existing entry) and 추가/삭제 (add or delete a line) in the input menu, and practise the modify path until it is automatic. After any correction, re-run the 합계잔액시산표 (trial balance) and confirm total debits equal total credits and the affected account balance moved by exactly the intended amount.
Treating exempt (면세) sales and zero-rated (영세율) sales as if they were taxable at 10%, or omitting them from the return entirely, so the 매출세액 (output tax) is overstated and the 과세표준 (tax base) breakdown is wrong.
Candidates memorise 'sales × 10%' and apply it to every sales line. They do not distinguish 면세 items such as unprocessed agricultural products, books, and medical services from 영세율 items such as exports, and they forget that exempt sales still must be reported on the return even though no output tax arises.
What to do instead
Classify each sales line by tax type before computing: 과세 (taxable), 영세율 (zero-rated), 면세 (exempt). Compute output tax only on the taxable base, and carry the exempt and zero-rated amounts into their own lines of the 신고서. Cross-check that the sum of the three bases equals total sales in the ledger.
Claiming input VAT (매입세액) on purchases that are non-deductible - for example on non-business assets, on entertainment expenses, or on invoices that lack the required registration details - and then not removing them in the 공제받지 못할 매입세액 adjustment.
Candidates see a purchase invoice with VAT and assume it is fully deductible. The non-deductible categories are a short list that is easy to skip under time pressure, and the software computes the deduction automatically from the input screen unless the candidate flags the line.
What to do instead
Memorise the main 불공제 categories and check every purchase line against them before finalising. Where the software has a flag or a separate adjustment screen for non-deductible input tax, use it, then confirm the 매입세액 line on the return equals total input VAT minus the excluded amount.
Computing the VAT payable without applying the 신용카드 매출전표 발행세액공제 and other deductions and credits, or applying them to the wrong period, so the final 납부세액 is wrong even though the base and output tax are correct.
Candidates stop once they reach 매출세액 minus 매입세액 and treat that as the answer. The return has a further sequence - 차가감납부세액, 공제·감면, 가산세 - and each step has its own line, so skipping one shifts every later line.
What to do instead
Work the return as an ordered checklist: base, output tax, input tax, deductions, credits and reductions, penalties, then final payable. Write the line order on scratch paper and tick each line as you fill it. Recompute the final figure from the return's own arithmetic rather than from memory.
Adding back expenses on the 세무조정 (tax adjustment) schedule that are already non-deductible by law, or failing to add back those that are, because the candidate cannot tell accounting expense from deductible expense.
Corporate tax practice requires converting accounting profit to tax income, and the add-back list (손금불산입) and deduction list (손금산입) are specific. Candidates who only know bookkeeping treat every expense recorded in the ledger as deductible and produce tax income equal to accounting profit.
What to do instead
Learn the representative 손금불산입 items - fines and penalties, non-business expenses, excess entertainment, excess depreciation - and the representative 손금산입 items - provisions, special depreciation. For each adjustment, write the reason and the legal basis next to the line so the schedule explains itself.
Applying the wrong tax rate or the wrong deduction schedule to a sole proprietor's income tax, for example using the corporate rate or ignoring the basic deduction and the earned income deduction when computing taxable income.
Candidates mix the corporate tax rate table with the individual income tax rate table, and they compute tax on total income without walking through the deduction sequence (소득공제 and 세액공제). The two regimes have different structures and different rate brackets.
What to do instead
For income tax, follow the sequence explicitly: total income, then 소득공제, then tax base, then the progressive rate, then 세액공제 and 감면, then 가산세. Keep the corporate rate table and the individual rate table on separate reference sheets and label which one applies before calculating.
Posting a transaction to the wrong side of the account - debiting where a credit belongs, or using the wrong account class - so the trial balance still balances but every affected statement is wrong.
Double-entry errors that preserve the balance are invisible to the 'debits equal credits' check. Candidates rely on that check as their only validation and never verify individual account balances against the source documents.
What to do instead
For each common transaction, fix the debit and credit pair in memory (for example, a cash sale debits cash and credits sales and output VAT). After posting, review the affected accounts line by line against source documents, not just the trial balance totals.
Confusing the order and effect of the 국세기본법 periods - 과세기간, 신고기간, 납부기간, and the various 가산세 deadlines - and therefore computing a penalty against the wrong due date or missing that an extension applies.
The National Tax Basic Act sets the framework that the individual tax laws then use, and candidates learn the VAT and corporate tax deadlines without the underlying general rules. When a question asks about a late-filing penalty or an amended return, they apply the wrong start or end date.
What to do instead
Build a one-page timeline that separates the general framework (과세기간, 신고·납부기간, 수정신고, 경정청구) from the specific deadlines of each tax. For every penalty question, write down the statutory due date and the actual filing date before computing the number of days.
Not using the software's built-in reports and instead recalculating balances by hand, which produces arithmetic slips and a trial balance that does not match the system's own output.
Candidates distrust the software or do not know which report to open, so they add ledger columns manually. The exam is scored on the software's output and on the printed statements, so a hand-computed figure that differs from the system is simply wrong.
What to do instead
Learn the report menu: 합계잔액시산표, 재무상태표, 손익계산서, 부가세신고서. Produce every figure from the report and use manual calculation only to verify. Before submitting, confirm that the printed statements reconcile to the ledger and that the VAT return ties to the sales and purchase accounts.