Item Types
The four item types in Trabalance and how each one behaves across inventory, accounts, and workflows.
Every item in Trabalance belongs to one of four types. The type is not cosmetic — it determines whether the item tracks inventory, which ledger slots it uses, and which workflows it can participate in. Setting the wrong type produces the wrong journal entries. Get this right at setup.
The Four Types
| Type | Purpose | Sub-Types Available | Tracks Inventory | Primary Use Case |
|---|---|---|---|---|
| Product | Physical goods you manufacture, purchase, and sell to customers | Make or Buy: Buy (purchase from vendors) or Make (manufacture in-house) | Yes | Sales invoices, delivery notes, GRNs, stock adjustments, production outputs |
| Service | Intangible work or time delivered to customers | Service Type: In-house (performed by internal staff) or Outsourced (contracted to external providers) | No | Service invoices, project billing |
| Material | Physical inputs used in production or consumed internally | Make or Buy: Buy (purchase from vendors) or Make (produce internally) | Yes | Cost cards, production batch inputs, internal consumption adjustments |
| Expense | Cost categories for purchases that expense directly to the P&L | Expense Type: Direct (attributable to production or services) or Indirect (overhead and administrative) | No | Purchase bills, expense claims, overhead lines on cost cards |
What "Tracks Inventory" Means
Product and Material items maintain a running stock balance. Every time one is purchased, delivered, adjusted, transferred, or consumed in production, the system updates the quantity on hand and its average cost. The inventory account on the balance sheet moves with every transaction. Product and Material items also carry a SKU and a Valuation Method. Four methods are offered on the form, but weighted average is the only one the costing engine implements — see Creating an item.
Service and Expense items have no stock count. When they appear on a transaction, the revenue or expense posts immediately — there is no intermediate inventory step. You cannot perform stock adjustments or view stock on hand for a Service or Expense item.
Account Mapping by Type
| Item Type | Income Slot | Expense Slot | Inventory Slot |
|---|---|---|---|
| Product | Sales Account — the income account credited when this item is sold. Default: Sales | Cost of Sales Account — debited when inventory is dispatched on a delivery note. Default: Cost of Sales | Inventory Account — the current asset account holding the stock value. Default: Inventory |
| Service | Service Revenue Account — credited on the invoice. Default: Sales | Service Cost Account — for tracking delivery cost and margin. Default: Cost of Sales | Not used |
| Material | Not used — materials are not sold | Material Cost of Sales Account — charged when material is consumed or written off. Default: Cost of Sales | Material Inventory Account — the current asset account holding the raw material stock value. Default: Inventory |
| Expense | Not used — expenses are not sold | Purchases / Expense Account — debited on every purchase bill containing this item. Default: Purchases | Not used |
Every slot is optional on the form: a blank slot resolves to the business default named above. A slot given an account of the wrong element is refused when the item is saved.
The Type can be changed by editing the item, and its ledger slots are re-resolved for the new type. Transactions already posted keep the accounts they were posted to, so changing the type of an item with history leaves that history on the old accounts. Prefer creating a new item with the correct type and marking the old one inactive.
Sub-Types
Sub-types are a further classification within a type, chosen with a two-option picker on the form: Make or Buy (Product, Material), Service Type (Service), or Expense Type (Expense). They appear on the Items list and item page and are used by Production: only Material items, and Product or Material items marked Make, can be picked as cost-card outputs.
Sub-types do not change the accounting behaviour — a Product marked Buy and one marked Make post to the same slots and track inventory the same way.
Choosing the Right Type
Use Product when the item is a physical good that has a purchase price, is counted in stock, and is eventually sold. A box of printer cartridges resold to customers is a Product.
Use Service when the item is time, skill, or intellectual output — not a physical thing that depreciates in a warehouse. A consulting day rate is a Service.
Use Material when the item is a physical input used in your production process or consumed internally without being sold. Sheet metal fed into a press is a Material. Office paper used by staff is also a Material (or an Expense if you prefer not to track it as inventory). Cost cards list Material items as their inputs.
Use Expense when the item is a cost category that should go straight to the profit and loss statement without any stock tracking. Internet service, office rent, airline tickets, and software subscriptions are all Expenses.