# IRD 90-Day Logbook Rules NZ (2026–27): 3-Year Validity, Work Utes & Kilometre Rates

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- **Jurisdiction / Region:** NZ
- **Last Verified:** Sun Nov 01
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- **Summary:** New Zealand IRD 90-day vehicle logbook rules (2026–27): 3-year validity, the 20% variation rule, Tier 1/Tier 2 km rates vs actual costs & work ute deductions.

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# IRD 90-Day Logbook Rules NZ (2026–27): 3-Year Validity, Work Utes & Kilometre Rates

**Short answer: Under sections DE 6 to DE 11 of the Income Tax Act 2007 and Operational Statement OS 19/04b, an IRD 90 day logbook is a continuous 90-day record of business trips and total vehicle distance used by a New Zealand sole trader to establish a vehicle's business-use percentage for up to 3 income years. You apply that percentage to either IRD's Tier 1/Tier 2 kilometre rates or actual vehicle costs on your IR3 (Box 24) and IR10 return. Without a logbook, deductions are capped at 25%.**

> **⚡ Instant NZ IRD 90-Day Logbook, Kilometre Rate & IR3/IR10 Toolkit ($NZD):** Calculate your NZ business vehicle deduction in the interactive **NZD Mileage & Logbook Calculator** right below, save your first 5 vehicle logs, Mitre 10 dockets, or NZBN tax invoices in the **[iCloud Web Workspace (5 Free Saves)](/keel/workspace/)** (or click **🔗 Embed / CSV Template**), explore the **[AU/NZ Tradie & Sole Trader App Store Edition](/keel/cpp/australia-nz-sole-traders/)** and **[Business Mileage Logbook Edition](/keel/cpp/business-mileage-logbook/)**, or **[Download Keel Free on the App Store ($0/mo)](https://apps.apple.com/us/app/keel-invoice-maker-receipts/id6786659713?ppid=8470921a-830e-47a3-abf5-bf0b1cce24ac)** (`au-nz-tradies`).

Every self-employed Kiwi builder, sparky, plumber, landscaper, and contractor driving a Hilux, Ranger, van, or station wagon faces the same audit question from **[Inland Revenue (IRD)](https://www.ird.govt.nz/income-tax/income-tax-for-businesses-and-organisations/types-of-business-expenses/claiming-vehicle-expenses)**: *can you prove your business-use percentage with a compliant 90-day logbook, or are you restricted to the 25% default ceiling?*

Below is the complete **2026–2027 New Zealand IRD 90-day logbook guide**, including what every entry must show, how the **3-year validity window** and **20% variation rule** work, when a sign-written work ute qualifies for **100% business use**, and how to link your logbook to your [IR3 tax return](/keel/nz-ir3-explained/), [IR3B/IR10 schedule](/keel/nz-ir3b-and-ir10-sole-trader-schedule-guide/), and [NZ GST returns](/keel/nz-claiming-gst-on-expenses/).

## Why does an IRD 90-day logbook matter so much for a NZ sole trader?

Under **section DE 8 of the Income Tax Act 2007**, if a sole trader uses a motor vehicle partly for business and partly for private trips and **does not keep a valid 90-day logbook** (or full year-round trip records), the maximum deduction you can claim is **capped at 25% of the vehicle's total running costs or kilometre-rate distance**—even if you actually drove the ute 85% of the time for trade jobs!

| Your Logbook Status | Maximum Business Use % You Can Claim on IR3 / IR10 | Impact on a Sole Trader Driving 18,000 Total km (15,300 Business km = 85% Work Use, Diesel Ute) |
|---|---|---|
| **Valid IRD 90-Day Logbook Kept** (Proving 85% business use) | **85%** (Your actual proved business share for up to 3 years) | Tier 1 (`14,000 × 85% = 11,900 km @ $1.30`) + Tier 2 (`3,400 km @ $0.38`) = **$16,762.00 tax deduction** |
| **No Logbook Kept** (Relying on default statutory rule) | **Capped at 25%** maximum (`s DE 8(2)`) | Capped at 25% of vehicle use (`4,500 km`) = **~$5,850.00 deduction** (**You lose over $10,900 in deductions!**) |
| **100% Work-Only Commercial Van / Ute** (Zero private use) | **100%** (Must still be able to prove zero private use) | **100% of actual fuel, RUC, rego, insurance, servicing & depreciation** (or 100% km rates) |

## What must a compliant IRD 90-day logbook include in 2026–2027?

Unlike Australia (which requires a 12-week logbook valid for 5 years), New Zealand's **sections DE 7 and DE 9 of the Income Tax Act 2007** require a logbook covering **at least 90 consecutive days** at a time of year that represents your normal average business use, and that logbook remains valid for **up to 3 years**.

To pass an Inland Revenue review, your 90-day logbook must record:

1. **The exact start date and end date** of the 90-consecutive-day test period;
2. **The vehicle's odometer reading at the start** of day 1 and **at the end** of day 90 (so IRD can see the **total distance travelled** for both business and private use during the 90 days);
3. **For every business journey during the 90 days:**
   - The **date** of the trip;
   - The **distance travelled (in km)** for that business trip (or start and finish odometer readings);
   - The **specific reason for the trip** (e.g., *"Site inspection & quote at 22 Dominion Rd, Mt Eden + PlaceMakers timber pickup"* — never just *"Work"*);
4. **Annual opening and closing odometer readings** (on **1 April** and **31 March** for a standard balance date) for each of the 3 income years the logbook is used, especially if you claim under the two-tier [NZ IRD mileage rate method](/keel/nz-mileage-rates-vehicle-expenses/).

### Worked Example: Calculating Your 3-Year IRD Logbook Percentage
Suppose an Auckland electrician records a 90-day logbook from **1 May to 29 July**:
- **Start odometer (1 May):** `42,100 km`
- **End odometer (29 July):** `46,600 km` $\to$ **Total 90-day distance = `4,500 km`**
- **Total recorded business trips during the 90 days:** `3,825 km`
- **3-Year IRD Business-Use Percentage:**
  $$\frac{3,825\text{ km (Business)}}{4,500\text{ km (Total)}} = 85.0\%$$

For the next **3 income years**, you claim **85.0%** of your annual vehicle expenses (or apply 85.0% to the IRD Tier 1/Tier 2 kilometre bands) and **85.0% of the 15% GST** on your vehicle running costs!

## What is the IRD "20% variation rule" that forces a new 90-day logbook early?

Under **section DE 7(2) of the Income Tax Act 2007**, your 90-day logbook is valid for up to **36 months (3 income years)**, **UNLESS** the business proportion of your vehicle's use changes by **more than 20 percentage points** (for example, dropping from `85%` down to `60%` because you moved house or bought a second vehicle). If your business use shifts by more than 20%, or if you replace the vehicle with a vehicle that has a different pattern of use, you must start a fresh 90-day logbook.

## How does the 90-day logbook interact with IRD Kilometre Rates vs Actual Costs in 2026–27?

Under **Operational Statement OS 19/04b**, once you have your 90-day logbook percentage, you choose either the **Kilometre Rate method** or the **Actual Cost method** when you first start using the vehicle for business—and once chosen, you must stick with that method for as long as you own that vehicle:

| Method | How the 90-Day Logbook % Is Applied (OS 19/04b) | Can You Also Claim 20% Investment Boost or Depreciation? | Best For Which Kiwi Tradie? |
|---|---|---|---|
| **Method A: IRD Two-Tier Kilometre Rates** (2026 rates: **$1.20/km Petrol**, **$1.30/km Diesel**, **$0.90/km Hybrid**, **$1.22/km EV** on Tier 1; then **37c / 38c / 24c / 23c** on Tier 2) | Multiply the **14,000 km Tier 1 band** by your **logbook business %** (e.g., `14,000 km × 85% = 11,900 km` at Tier 1 rate); any remaining business km above `11,900 km` are claimed at the Tier 2 rate | **No** — IRD's Tier 1 kilometre rates already include a built-in vehicle depreciation component | High-mileage sole traders driving reliable utes/vans or second-hand vehicles where simplicity beats keeping every fuel docket |
| **Method B: Actual Vehicle Running Costs + Depreciation** | Claim your **logbook business %** (e.g., `85%`) of every fuel, RUC (Road User Charges), WoF, rego, insurance, tyre, and servicing receipt **PLUS** `85%` of annual depreciation | **Yes!** If you bought a brand-new work ute over $1,000 on/after 22 May 2025, you can claim `85%` of the **20% Investment Boost** upfront plus `85%` of **20% DV depreciation** | Tradies buying a brand-new $45k–$70k ute eligible for the [20% Investment Boost](/keel/nz-low-value-asset-write-off-tradies-guide/) or vehicles with high RUC/repair costs |

## Does a sign-written dual-cab ute automatically get 100% tax deduction in NZ without a logbook?

**No—this is a classic Kiwi tradie myth.** Even if your dual-cab Ranger or Hilux has your business logo on the doors and toolboxes on the tray, the **FBT work-related vehicle rules** apply to companies paying Fringe Benefit Tax—**not** automatically to an unincorporated sole trader under **Subpart DE**!

For a **sole trader**, you can only claim **100%** of a ute or van without a 90-day logbook if the vehicle is **genuinely used 100% for business and 0% for private trips** (for example, it is parked at your yard/home and you have a separate private family car used for all weekend, school, supermarket, and fishing trips). The moment you use that sole-trader ute for weekend towing or family errands, it is a mixed-use vehicle and requires a **90-day logbook** to avoid the 25% cap.

Remember: under **section HB 1 / Subpart DB**, travel from home to a fixed yard or office is normally private, **unless** your home is your genuine base of business operations (where you do quotes, invoicing, and store bulky trade tools/ladders that cannot be carried on public transport) and you travel directly from home to fluctuating client jobsites.

## Frequently asked questions

**How long do I have to keep my 90-day vehicle logbook in New Zealand?**

Under section 22 of the Tax Administration Act 1994, you must retain your 90-day logbook for 7 years after the end of the last income year to which that logbook relates. Because a 90-day logbook can be used to support your business-use percentage for up to 3 income years, you must keep that logbook record for up to 10 years from the day you recorded it (3 years of active use plus 7 years of statutory retention). See our [NZ 7-year record keeping guide](/keel/nz-ird-7-year-record-keeping-sole-trader/).

**Do I need to record private trips in detail in my IRD 90-day logbook?**

No. You only need to record the date, distance, and specific business reason for each business journey, plus the vehicle's opening odometer reading on day 1 and closing odometer reading on day 90. The difference between total kilometres travelled (closing minus opening odometer) and your summed business kilometres automatically gives your private kilometres.

**Can I claim 15% GST on my fuel and RUC if I use the IRD kilometre rate for income tax?**

No—you cannot use the IRD income tax kilometre rates to calculate GST credits. For GST returns, a GST-registered sole trader claims 15% GST (3/23rds) on actual tax invoices/taxable supply information for fuel, RUC, tyres, servicing, and insurance multiplied by your 90-day logbook business-use percentage.

**What happens if I don't keep a 90-day logbook for my work vehicle in New Zealand?**

Under section DE 8(2) of the Income Tax Act 2007, if you do not keep a valid 90-day logbook (or complete year-round trip records) for a mixed-use vehicle, Inland Revenue caps your maximum business deduction at 25% of the vehicle's running costs or kilometre-rate distance.

**When must I start a new IRD 90-day logbook before the 3 years are up?**

Under section DE 7(2), you must complete a new 90-day logbook early if the business-use proportion of your vehicle changes by more than 20 percentage points (for example, dropping from 85% to 60%), or if you replace the vehicle with one that has a different pattern of business vs private travel.

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