Closing entries are posted to the post-closing trial balance.
The post closing trial balance is a list of all accounts and their balances after the closing entries have been journalised and posted to the ledger.
It consists of the cash, assets, account receivable, account payable and all other expenses and revenues and their values against debit or credit column and in the end credit should be equal to debit.
Next step is to record any necessary reversing entries.