Baja California Sur → Sonora · Carretera Transpeninsular 1
Coming back from La Paz, Baja California Sur, to Hermosillo, Sonora, the return leg also clocks roughly 690 km (429 miles) typically along Carretera Transpeninsular 1, but the traffic picture shifts considerably compared with the outbound segment. La Paz, the capital sudcaliforniana sobre el Mar de Cortés y nodo del ferry Topolobampo-La Paz, fades behind the wheel while the vehicle pushes back toward Hermosillo, the capital sonorense y sede de la planta automotriz Ford Hermosillo, often after a full day of meetings, site visits, or prospecting calls. Plan 7h 40m plus a generous buffer against evening congestion, particularly on Fridays, holiday eves, or after major sporting events. Driver fatigue is the dominant concern returning home; mandatory rest breaks every two hours are non-negotiable. Fuel spend on the return stays near MXN 1391.50 for 57.5 liters (15.2 gallons). The corresponding reimbursement on the way back reaches MXN 4485.00 at MXN 6.50/km. Combine both legs on a single Clara receipt to document the full round-trip cleanly, with separate timestamps for transparent audit defense. For the US professional driving the 690 km (429 mi) between La Paz and Hermosillo, reimbursement of MXN 4485.00 stays non-taxable to the employee when the employer follows an accountable plan under Treas. Reg. §1.62-2 and reimburses at or below the IRS standard mileage rate. US employers generally reimburse at the IRS standard mileage rate so the payment stays non-taxable to the employee under Pub. 463. Keep the IRS-compliant expense report (Form 1040 Schedule C, line 9) alongside the fuel receipt from any EIA-tracked retail station network pump used along the leg; Internal Revenue Service (IRS) examiners pull contemporaneous mileage logs first when auditing Schedule C unreimbursed business expenses, and the La Paz→Hermosillo corridor must show date, business purpose, and odometer readings.