Four rows, four calendars: which file updates your trip-cost sheet

The month closes, you open the trip-cost sheet, and its four rows have gone stale at four different moments: fuel in mid-August, motor vehicle tax on the last day of December, the inspection fee at the turn of the year, depreciation not once since last year. The sheet is doing exactly what it was built to do; the trouble is that every row lives on its own calendar, and once those calendars get mixed together the cost per trip lands either under or over the truth.

The real work in a sheet like this lies in knowing where each row is fed from, more than in adding the figures up. Fuel traces back to a Presidential Decision, the tax to a General Communiqué, the inspection fee straight to a clause of the traffic law, and depreciation to a rate that has sat in the same place for years. Write the file name and the date of the version you consulted beside each row, and three months later the question "where did this number come from" answers itself.

A footnote governs the fuel row

Open table (A) of list (I) under Excise Duty Law No. 4760 and diesel turns up on more than one row: the table runs by G.T.İ.P. number, separates gas oils by their sulphur content by weight, and quotes the duty per litre. On the diesel rows, footnote 48 sits next to the amount, recording that the excise duty on this type of diesel was set by Article 1 of the Decision annexed to Presidential Decision No. 11606 of 12/8/2026, published in Official Gazette No. 33339 of 13/8/2026 and effective on its date of publication, and it sends you to that Gazette issue to read the amounts. Copy the figure standing in the cell and you have copied it without reading the note attached to it.

Three places tell you which copy you have in front of you. The Revenue Administration names its list file by the date it takes effect, so the August copy carries 14/8/2026 in its name; the same date is repeated on the first page as "Yürürlük Tarihi", and a note at the foot of the table states which Presidential Decision, by date and number, the file was updated under. If instead you opened the law text on mevzuat.gov.tr, the warning printed just above the lists points you to the Legislation Monitoring Table at the end of the Law, where every instrument that has amended lists (I), (II), (III) and (IV) is set out with the date and number of the Official Gazette that carried it, so the closing lines of that table date your copy for you. Since the sliding-scale mechanism can move the file within days, those three marks are what tell you whether a cell that was right in mid-August still holds in September.

Article 7/A of the same Law rewrites the fuel row for one kind of run. Diesel under the two G.T.İ.P. numbers in list (I) is exempt from the duty when it is delivered, at border gates designated by the President and only on the way out of the country, into the tanks of trucks, tractor units and refrigerated semi-trailers carrying goods bound abroad under the export regime of the Customs Law; the article ties the exemption to the standard tank capacity of the vehicle and of the cooling unit. The fuel row of a van running domestic distribution and the fuel row of a tractor unit pulling an export load therefore cannot share one cell, and splitting the sheet by type of run costs less than hunting for the discrepancy at month end.

Tax and inspection stir in the same corner of the year

The motor vehicle tax row settles once a year, through the General Communiqué published in the closing days of December, and the trap is doing the indexation arithmetic on your own. Motor Vehicle Tax General Communiqué (Series No: 58) states in the second paragraph of Article 3 that although the 2025 revaluation rate was determined as 25.49 percent, Presidential Decision No. 10783 of 30/12/2025 set 18.95 percent for the 2026 tax amounts under tariffs (I), (I/A), (II) and (IV); the first paragraph of the same article, quoting Article 10 of Law No. 197 in full, shows that the President may fix a new rate within a band around the revaluation rate. The tariff tables in the Communiqué print the amounts already worked out, so nobody has to redo the multiplication here; the figure is there to be read. Under the second paragraph of Article 4 vans and trucks belong to tariff (II), which means a row confused with the car-side tariffs (I) and (I/A) carries an error through the whole year.

The base for the inspection fee still stands in the law in 2004 lira. Article 35 of Highway Traffic Law No. 2918 names 100 million lira for buses, trucks, tractor units and tankers, and 75 million lira for cars, minibuses, vans, special-purpose vehicles, off-road vehicles, trailers and semi-trailers, value added tax excluded, then adds that these amounts are raised by the revaluation rate determined and announced for that year under the Tax Procedure Law, with effect from the start of each calendar year. The same paragraph also drops the small remainder from the figure so calculated and lets the President raise or lower the applied inspection fees at set intervals, so the number your cell needs is whatever years of indexation have made of the figure printed in the law.

The same article puts a price on lateness: for every month an inspection is overdue the fee is collected with 5 percent added, and part months count as whole months. Take a truck whose inspection falls due on 20 April and reaches the station on 22 May, and those two days of overrun push the delay into a second month, so this row advances in whole months. The rest of the article assigns the whole of the 5 percent surcharge to the Treasury share paid over to the tax office, which leaves nothing for the station to negotiate away. How successive months stack on one another is not spelled out in the text, so the sound practice is to carry the vehicle's inspection date into the sheet instead of closing the cell with a single figure.

While the fee cell grows by 5 percent, the real cost of a month's delay gathers where the sheet has no row at all. Article 34 of the same Law provides that taking an uninspected vehicle onto the road brings an administrative fine on the owner; that such vehicles are then given time to present themselves for inspection on the terms set in the Highway Traffic Regulation; and that once that period ends, vehicles still driven without inspection, or reported unsafe, are barred from traffic and sent to the nearest inspection station. The fines themselves travel with the annual revaluation as well, so the number to enter for that month's trips cannot be worked out while the inspection date is missing from the sheet.

Depreciation holds its place all year. Depreciation is the row that stays still all year, which is the comfortable part of it. The Depreciation Rates Table issued under Article 315 of the Tax Procedure Law carries light trucks and vans at 4 years and 25.00 percent (row 6.3, General Communiqué No. 333), and trailers together with the containers carried on them, semi-trailers included, at 6 years and 16.66 percent (row 6.13, General Communiqué No. 458). Because each row closes with the serial number of the Communiqué that introduced it, the table itself tells you how long an entry has read the way it reads now. The wording of the entry deserves as much attention as its rate: row 6.3 defines a light truck by unladen weight, heavy goods trucks above that threshold sit on the next row with a longer useful life, and the tractor unit stands apart from the trailer row on a life of its own. Since only a new General Communiqué moves those entries, this is the one item that should read identically from January to December; monthly drift here points at the arithmetic.

Added together, these rows are what refrigerated vehicle running cost actually means, and we lay the whole calculation out step by step on its own page.