Guanajuato → San Luis Potosí · Autopista 45D Salamanca-Querétaro
What does it actually cost to drive from Salamanca, Guanajuato, to San Luis Potosí, San Luis Potosí? The hard numbers: 222 km (138 miles) of pavement primarily along Autopista 45D Salamanca-Querétaro, 2h 28m behind the wheel, and roughly MXN 447.70 in fuel alone — that is 18.5 liters (4.9 gallons) of gasolina Magna at a 24.20 MXN/liter benchmark. Anyone leaving Salamanca, the sede de la refinería Ing. Antonio M. Amor de Pemex, typically carries samples, signed proposals, or service equipment to deliver in San Luis Potosí, the capital potosina y nodo logístico que conecta el Bajío con el norte del país, and aims to be home the same evening. It is worth confirming whether the haul fits inside your daily hours-of-service window or whether an overnight at a midpoint hotel makes more sense. Applying the tarifa promedio de mercado mileage rate of MXN 6.50/km (MXN 10.46/mile), the gross outbound reimbursement settles at MXN 1443.00. Attach the visit purpose, client name, and plate number to the Clara receipt so the journal entry lands directly in the business-travel expense account. For the UK professional driving the 222 km (138 mi) between Salamanca and San Luis Potosí, reimbursement of MXN 1443.00 fits the subsistence allowance regime when paid at or below HMRC AMAP rates of 45p per mile for the first 10,000 business miles in the tax year. UK firms reimburse at HMRC AMAP rates (45p / 25p per mile) so the payment stays free of PAYE and NIC under approved mileage allowance payments rules. Retain a VAT receipt accepted by HMRC for input-tax recovery from the BEIS-tracked forecourt network forecourt used to refuel; His Majesty's Revenue and Customs (HMRC) compliance officers cross-reference fuel VAT receipts with the P11D return when reimbursement exceeds the approved rate. Excess paid above AMAP on the Salamanca→San Luis Potosí run must be reported via PAYE settlement agreement or it becomes a benefit-in-kind on the employee's tax code.