San Luis Potosí → Guanajuato · Autopista 57D México-San Luis Potosí
Returning from San Luis Potosí, San Luis Potosí, back to Salamanca, Guanajuato, the itinerary retraces the same 222 km (138 miles) of the outbound segment, predominantly via Autopista 57D México-San Luis Potosí, adding another 2h 28m to the corporate odometer. Unlike the outbound leg, the homeward journey is usually executed at the close of the business day, when heavy truck traffic, accumulated fatigue, and dropping daylight all demand sharper focus. Anyone hoping to ease the arrival back into Salamanca, the sede de la refinería Ing. Antonio M. Amor de Pemex, may consider an overnight stop in a midpoint town and splitting the haul into two shorter stints. Fuel expense holds steady near MXN 447.70, totalling roughly 37.0 liters for the entire trip when added to the outbound segment. The return reimbursement reaches MXN 1443.00, doubling the aggregate payout for the full journey. Log each leg separately in the Clara receipt, with distinct timestamps, so the paperwork accurately mirrors the vehicle's actual movement. For the Canadian professional driving the 222 km between San Luis Potosí and Salamanca, reimbursement of MXN 1443.00 stays excluded from T4 employment income provided the per-kilometre rate matches the CRA's reasonable allowance benchmark for the province. Canadian employers typically reimburse at the CRA reasonable per-kilometre rate (61¢ for the first 5,000 km in 2024) so the payment is excluded from T4 employment income. Keep the GST/HST-compliant fuel receipt from any NRCan-tracked retail network station used during the trip — Canada Revenue Agency (CRA) auditors regularly verify fuel-receipt GST/HST when reviewing T2200 declarations of conditions of employment. The San Luis Potosí→Salamanca mileage must be logged with date, business purpose, opening and closing odometer readings inside the corporate expense system before month-end close to remain deductible.