A journal entry records a single transaction in the books using double-entry bookkeeping. Every entry has a date, a description, and at least one debit and one credit that are equal in total.

Steps:

  1. Identify the transaction. What happened? Cash was received, an expense was incurred, a liability was created, etc.
  2. Determine which accounts are affected. Every transaction touches at least two.
  3. Decide which accounts are debited and which are credited. Remember: assets and expenses increase with debits; liabilities, equity, and revenue increase with credits.
  4. Verify the entry balances — total debits must equal total credits.
  5. Record the entry with the date, accounts, amounts, and a brief description.

Example — purchased office supplies for $300 cash:

AccountDebitCredit
Office Supplies Expense$300
Cash$300

Example — received $5,000 from a client on account:

AccountDebitCredit
Cash$5,000
Accounts Receivable$5,000

Common mistakes:

  • Reversing debits and credits (debiting what should be credited)
  • Forgetting to include all affected accounts in compound entries
  • Recording the wrong amount (especially with tax-inclusive vs. tax-exclusive amounts)
  • Missing the date, making the entry hard to place in the correct period