St. Louis and McAllen have a similar cost of living.
When comparing St. Louis, MO and McAllen, TX, the overall cost of living indices are 66 and 66 respectively (national median = 100). Rent is comparable in both cities, with less than $50/month separating them.
Median household income is $4,886/year higher in McAllen. Home values also differ significantly — the median in St. Louis is $185,100 compared to $173,800 in McAllen.
Texas has no state income tax, giving McAllen residents a significant tax advantage over Missouri's 4.95% rate.
St. Louis vs McAllen — common questions
Other cost of living comparisons for St. Louis and McAllen