Dictionary / BOM
What does BOM mean in accounting?
Quick definition
GeneralBeginning of month. This term guides how bookkeepers record, classify, and explain related transactions in routine financial reporting.
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Examples
Rent due BOM is the first of the month
You run a yoga studio. The landlord emails that studio rent of $2,400 is due BOM. That means September 1, not August 31 and not September 4 when you open the mail. Enter a bill dated September 1 to the landlord in QuickBooks Online or Xero, coded to rent expense. If you date it August 31 because you already knew the amount, August's P&L takes September rent and September looks cheap.
A parts list labeled BOM is not a date
You run a cabinet shop. On June 3 the shop hands you a printout titled BOM for a kitchen job: 12 maple doors, 36 hinges, and 2 gallons of stain ($1,160 of parts). You almost file it as the June 1 beginning-of-month inventory count. That sheet is a bill of materials, the recipe for one job, not a date. Opening inventory for June is the count you took on June 1; keep the parts list with that job's folder so you issue those quantities when you build.
Why it matters
BOM is shorthand for the first calendar day of a month. It shows up on leases, recurring vendor bills, and inventory count sheets when someone needs a clean start date, not as a ledger account. Mix it with end of month and a first-of-the-month charge drops into the prior accounting period; mix it with a bill of materials and you read a date as a parts list. When a note says BOM, check whether the next word is a month or a list of parts.
Further reading
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What is BOM in bookkeeping?
Beginning of month.
When should I use BOM?
Use BOM when the transaction facts match its definition and you need the ledger and financial statements to reflect the correct account and period.
What is a common mistake with BOM?
BOM is used for bom entries, while Bad Debt covers a related but distinct bookkeeping purpose. Review both terms before posting unusual transactions. A common mistake is applying it by label only instead of checking the underlying transaction details.