会计账户的结构分为两个基本部分，一部分反映增加，另一部分反映减少。其中，登记的本期增加金额，称为本期增加发生额；登记的本期减少金额，称为本期减少发生额；增减相抵后的差额，称为余额。余额按照表示的时间不同，分为期初余额和期末余额，其具体内容如下：

1.期初余额 Opening balance

期初余额（Opening balance）是指期初已存在的账户余额。期初余额以上期期末余额为基础，反映了以前期间的交易和上期采用的会计政策的结果。1.期初已存在的账户余额是由上期结转至本期的金额，或是上期期末余额调整后的金额。通常，期初余额是上期账户结转至本期账户的余额，在数额上与相应账户的上期期末余额相等。但是，由于受上期期后事项、会计政策变更、前期会计差错更正等诸因素的影响，上期期末余额结转至本期时，有时需经过调整或重新表述。2.期初余额反映了以前期间的交易和上期采用的会计政策的结果。期初余额应以客观存在的经济业务为根据，是被审计单位按照上期采用的会计政策对以前会计期间发生的交易和事项处理后的结果。3.期初余额与注册会计师首次接受委托相联系。广义地讲，注册会计师无论是首次接受委托对被审计单位的财务报表进行审计，还是执行连续审计业务，都会涉及期初余额审计。但在连续审计业务中，注册会计师在当期审计中通常只需关注被审计单位经审计的上期期末余额是否已正确结转至本期，或者是否在适当的情况下已作出调整或重新表述，很少需要再实施其他专门的审计程序。

The opening balance is the balance that is brought forward at the beginning of an accounting period from the end of a previous accounting period or when starting out. The opening balance is the amount of funds in a company's account at the beginning of a new financial period. It is the first entry in the accounts, either when a company is first starting up its accounts or after a year-end. In an operating firm, the ending balance at the end of one month or year becomes the opening balance for the beginning of the next month or accounting year. The opening balance may be on the credit or debit side of the ledger. 相关例句如下，可供参考：

例句1

Opening balances are most important when a company finishes an accounting year, and ends up with a closing balance - the last balance in the accounts. This balance is carried forward to the new financial year accounts and then becomes the opening balance - the first entry in the new accounting period.

在公司结束一个会计年度时，其期初余额是最重要的，并以期末余额结束-账户中的最后一笔余额。该笔余额结转到新的财政年度账户，然后成为期初余额，即新会计期的第一个分录。

例句2

Any interest charged on debit balances which is not paid at the close of an interest period will be added to the opening balance for the next interest period.

利息期间期末未付的借方余额的利息将加至下一利息期间的期初余额。

例句3

The opening balance is used in the beginning of a financial plan on the opening balance sheet. The length of time that a company has been operating determines what should appear on the opening balance sheet.

期初余额用于期初资产负债表上财务计划的开始。公司经营时间的长短决定了期初资产负债表上应涵盖的内容。

2.期末余额 Closing balance

期末余额（Closing balance）是指期初余额加本期增加发生额和本期减少发生额相抵后的差额，也就是在一定时期的期末结出的账户余额。

期末余额=期初余额+本期增加发生额-本期减少发生额

资产负债表各项目“期末余额”的数据来源，可以通过以下几种方式取得：1.直接根据总账科目的余额填列。2.根据几个总账科目的余额计算填列。3.根据有关明细科目的余额分析计算填列。4.根据总账科目和明细科目的余额分析计算填列。5.根据总账科目与其备抵科目抵销后的净额填列。

A closing balance is an amount of funds your business has at the end of a particular chosen accounting period — a day, a month, a quarter or a year. Once you calculate the closing balance, you pass it on the next accounting period and the figure becomes the opening balance for that period. For example, if your closing balance is £15,000 for 31 December 2019, your opening balance for 1 January 2020 will also be £15,000. A closing balance is also referred to by abbreviations c/d and c/f, meaning ‘carried down’ and ‘carried forward’ as it is moved on to the next accounting period. 以下为相关例句：

例句1

A closing balance is the amount remaining in an account within your chart of accounts, positive or negative, at the end of an accounting period or year end. It's easy to stay on top of the balance of your accounts with online accounting software like Debitoor.

期末余额是在会计期末或年末会计科目表账户中的余额（或正或负）。使用Debitoor等在线会计软件易于助你时刻掌握账户余额。

例句2

For your business’s assets and liabilities, or in other words what your business owns and what it owes, the closing balance at the end of the last period will be the same as the opening balance at the start of the new one.

对于企业的资产及负债，或换言之，企业拥有的及它所欠的，最后一期结束时的期末余额将与新期开始时的期初余额相同。

例句3

The balance of a bank account at the end of a period, such as a month or year. If the closing balance is listed on a bank statement, it indicates the closing balance on the date the statement was printed.

银行账户在一个时期结束时的余额，如一个月或一年。若银行对帐单上列出了期末余额，则表示打印对帐单当日的期末余额。