Tax collected is a liability
When you invoice a customer for goods plus tax, the goods go to sales income and the tax goes to a Sales Tax Payable account. Your income is the sale, not the total of sale plus tax. Mixing them overstates revenue and understates cash available.
Software handles the split automatically if tax settings are correct. Spot-check a few invoices to confirm.
Common ways this account goes wrong
The balance may drift when sales are entered in a lump sum from a register report that includes tax inside the total, when tax is entered as income, when refunds are recorded without reversing tax, or when payments to the state are booked as expenses. Each leaves the liability wrong.
Payment processors that deposit net of fees and tax add another layer. Reconcile the processor reports to the books separately.
Reconcile to the return
At each filing, compare the tax collected on the sales report for the period to the amount shown on the return and to the change in the liability account. After the payment is recorded against the liability, the balance should be close to zero for that period, except for tax collected after the period ended.
Differences might be rounding, timing or errors. Document the reason for each. Do not plug.
Handle discounts, returns and bad debt
A returned item should reverse both the sale and the tax. A discount reduces the taxable amount in most states. Uncollected invoices with tax may have special rules for recovering the tax. Raise it with your advisor before writing them off.
Gift cards and deposits are timed differently. Ask your advisor when they become taxable.
Keep the money available
Because the cash belongs to the state, many owners keep collected tax in a separate savings account. A liability balance of several thousand dollars with a bank balance far below it is a warning sign.
Record penalties and interest paid to the state in their own expense account, apart from the tax.
Month-end test for the liability
Take the taxable sales for the month, multiply by the combined rate you charge, and compare the result to the credit activity in the liability account. A large gap means invoices were set up with the wrong tax code or sales were entered without tax. This sanity check takes minutes and catches most setup errors.
If you operate in more than one jurisdiction, run the test for each one separately, because an error in one can hide behind a correct balance in another.
Finally, remember that a clean liability account is also a sign of a healthy business process. If the balance reconciles every period, you can answer a state agency question in minutes. If it never reconciles, each question becomes a project. Make the tie-out a standing item in your month-end close, next to the bank reconciliation.
Common questions
Can I pay the state from the operating account?
Yes, but record the payment against the liability, not as an expense.
How do I fix a past mistake?
Identify the periods affected and consult your advisor about whether to file amended returns. Then correct the books.
Should I prepay tax?
Generally no. Pay what the return shows is due.
This guide is general information, not tax, legal or accounting advice. Rules, fees and due dates change; check with the IRS, the NJ Division of Taxation or a licensed professional for your situation.