• Criteria 1: Pew Research defines middle-income Americans as those whose annual household income is two-thirds to double the national median (adjusted for regional cost of living and household size). For a family of three, that ranges from $40k to $120k for 2018 incomes.
• Criteria 2: According to 2019 numbers, the range for a mid-middle-class family of three was an income of $53,413 to $106,826 (twice). The same three-person family needed an income between $106,827 and $373,894 to be considered upper-middle-class.

Note the Pew research calculator shows that even with $180k pre-tax income I’m still in the middle class not the upper class. This is consistent with my self-assessment.

https://singlemotherguide.com/single-mother-statistics/ shows median income for single mothers (45k) vs couples (94k). This site is presumably accurate on single-mothers.

2022 UK figure: lower-midclass income is GBP [18-25k]/Y, up to USD 31k