Double declining balance depreciation, explained and calculated

Double declining balance is the most aggressive of the common accelerated methods. It is a declining-balance approach, like diminishing value, but it uses double the straight-line rate, then switches to straight-line near the end so the asset finishes inside its useful life. This page explains both halves, walks through a worked example, and shows how Cohiva Control computes it.

How double declining balance works

The method has two phases. While the declining-balance charge is the larger of the two options, it applies:

• Monthly charge equals current book value times (2 divided by useful life in years), divided by 12.

As the book value falls, that charge shrinks. Eventually the straight-line charge on the remaining life and remaining depreciable amount becomes the higher figure. At that point the method takes the straight-line charge instead, so the asset is fully depreciated down to its residual value within its useful life rather than trailing off.

A worked example

The calculator above uses a cost of 42,000, a residual value of 2,000 and a 60-month, five-year life. The straight-line rate is 20 per cent a year, so double declining balance uses 40 per cent. The first month charges 1,400.00, which is 42,000 times 40 per cent divided by 12, leaving a book value of 40,600.00. The second month charges 1,353.33 on the smaller base, then 1,308.22, and the charge keeps falling. Later in the schedule, once straight-line on the remaining life gives more, the method switches to even charges to finish at residual. The figures come from the product’s depreciation engine, so they match what Cohiva Control posts.

When to use it

Reach for double declining balance when an asset loses most of its value very early and you want depreciation to reflect that more sharply than diminishing value does, while still landing cleanly thanks to the straight-line switch. If you prefer a smoother accelerated taper, sum of years digits is an alternative; if even charges are fine, straight-line is simpler.

How Cohiva Control computes it

Cohiva Control runs both phases through the same engine the product uses internally, including the comparison that triggers the switch to straight-line. Money is a fixed-precision decimal rounded half up, never a floating point number, and the residual-value floor ensures the asset never depreciates below residual.

Each monthly run writes to an append-only depreciation ledger and can post a journal to Xero, QuickBooks, NetSuite or Cohiva Crunch. The run is idempotent, posting state is tracked separately from the immutable ledger row, and the asset you depreciate is the same asset your team maintains.

Part of the Cohiva platform

Cohiva Control is part of the Cohiva platform. Leisure operators often run it with Cohiva Complex, and finance teams connect it to Cohiva Crunch for the general ledger. Explore the platform at www.cohiva.app.