A Mechanical Engineer earning $120K/year in South Carolina takes home $88,203 after all taxes. That’s $7,350/month, with an effective tax rate of 26.5%.
The estimated median salary for Mechanical Engineers in South Carolina is $85K (adjusted from the national median of $92K using South Carolina’s cost-of-living index of 92). At $120K, you’re earning 41% above the state-adjusted median for this profession.
This salary places you in the upper tier for Mechanical Engineers in South Carolina, likely reflecting senior-level experience, specialized skills, or management responsibilities. At this level, tax optimization becomes increasingly important — the difference between the best and worst states at $120K is $10,374/year.
Filing as married filing jointly on $120K (single earner) saves you $7,585/year ($632/month) compared to filing single. This marriage bonus comes from the doubled standard deduction ($32,200 vs $16,100) and wider lower brackets.
Mechanical engineers who hold a Professional Engineer (PE) license can deduct licensing and continuing education costs if self-employed. Patent bonuses or invention awards from your employer are taxed as ordinary income. Engineers who travel to job sites or manufacturing facilities should track mileage if self-employed — the 2026 standard mileage rate can add up to significant deductions. If you receive a signing bonus when changing employers, it’s withheld at the 22% supplemental rate regardless of your actual bracket.
At #25 out of 50 states for take-home pay on a $120K salary, South Carolina falls in the upper half of states. You’d keep $4,992 more per year in Alaska (#1), or $416/month.
After adjusting for cost of living, South Carolina ranks #20 in purchasing power. That’s a boost from #25 in raw take-home — South Carolina’s lower costs stretch your paycheck further.