← Back to blog

Why GPS Alone Isn't a Mileage Log — What IRS and CRA Actually Look For

The pitch behind most automatic mileage apps is simple: leave the phone in your pocket, swipe later, export a number at tax time. That workflow is convenient. It is also why so many drivers find out, too late, that a reviewer wanted a logbook — not a trail of GPS points that sometimes skipped a leg, flipped a classification, or never recorded what the dash said on 1 January.

This is not an argument against automatic detection. Carspel has Auto Trip for that, and we are honest about the battery trade-off. It is an argument that detection is not the record. The record is the structured fields you can still explain a year later.

What a mileage log usually has to show

We are not your tax adviser, and requirements differ by country and by how you claim. Across IRS standard-mileage records and a CRA-style automobile logbook, the same gaps keep showing up in real complaints: no opening or closing odometer for the year, no written purpose, no destination, and no way to separate commute from business from medical from charity.

A map can show that the phone moved from one car park to another. It cannot, by itself, tell a reviewer whether that was a client visit, a school run, or a clinic appointment 90 km from home. Those are different categories, and in more than one country they are different rates — or not a rate at all.

Odometer is the unfashionable field that still matters

GPS distance is an estimate. Dash odometer is what most logbook instructions still talk about: the reading at the start of the year, the reading on the trip, the reading at the end. When those numbers are missing, a reconstructed GPS total is harder to defend — especially if the app also missed a drive after a phone update or a battery-saver change.

Carspel lets you fill trip distance from start and end odometer when you have them, and the tax-year PDF can include a year-opening appendix — labelled “Opening confirmed” only when you saved a snapshot on that date. We will not pretend a reconstructed GPS chain is the same thing as a dash reading you wrote down.

Categories are not a note on Personal

In the United States, the IRS publishes separate standard mileage rates for business, medical (and qualifying military moving), and charity. Charity is fixed by statute; the others move with cost studies — and in 2026 they even moved mid-year. In Canada, the CRA automobile allowance is a business per-kilometre table. Medical travel is a different credit, with a one-way distance test that is usually described as 40 km before vehicle costs can enter the picture and 80 km before meals and lodging may also apply. Equivalent care must not have been available nearer home. That is not something an app should “auto-qualify.”

MileIQ can tag Medical or Charity — often as a longer gesture, or as Purpose text on a Personal trip. We import those keywords into Carspel categories. The difference is what happens next: Carspel stores Business, Medical, Charity, Commute, and Personal as first-class fields, then the country-aware export either prices the row or honestly refuses to.

On a US trip-log export, the optional IRS column can apply the published business, medical, or charity rate to that row and leave personal and commute blank. The 2026 column still uses a simplified annual table — not the July 2026 mid-year split — so confirm the current cents-per-mile at irs.gov before you treat the dollar as the number you will file. On a Canada export, business kilometres can use the CRA allowance bands; medical kilometres are listed with that 40/80 km footnote and no medical dollar is invented. Insights on the Home screen is even narrower: it prices business kilometres only.

Confirm the draft. Do not trust the swipe alone.

The other failure mode drivers describe is silent: a trip never appears, or a business tag flips back to personal, or a “teleport” joins two places that were never one drive. Background location is at the mercy of the phone. That is true for every app in this category, including ours.

Carspel's Auto Trip (Family, Ultimate, and Trial) detects drives in the background and waits for you to Confirm the draft and set the category. Basic uses Live trip while Add trip is open, or a typed trip. Neither workflow claims we cannot miss a drive. The honest product is a log you review — plus fuel, charging, and service on the same timeline — not a black box that files a deduction for you.

What we will hand you, and what we will not

The trip-log PDF and CSV roll up distance by category, keep commute out of the deductible-mileage subtotal where that language applies, and can attach an illustrative official-rate column for the United States, Canada, Australia, the United Kingdom, Ireland, New Zealand, and South Africa when a table is seeded. Every other country still gets the full log without a dollar column. We do not file the return. We do not promise the export will survive every audit. We do give you and your CPA the same structured fields a logbook is supposed to have.

If you are switching, import the MileIQ trip CSV so the history you already have is not left behind. Then keep the habit in Carspel. The conversion page for that workflow is Defensible trip logs for tax records — odometer, categories, and an export that stays quiet when we do not have the rule.

Related reading