take one’s belt in a notch
take (one's) belt in (a notch (or two))
To reduce, restrict, or limit one's budget or expenses; to live more modestly or make financial sacrifices. (Alluding to having a thinner waist line due to having less to eat.) It's pretty galling to see the CEO driving up to work in a brand new company car while the rest of us are being told to take our belts in to help save the business. With your mother out of work, we're all going to have to take our belts in a notch or two for a little while. I really love my new job, but it pays a lot less so I've had to start taking my belt in a notch.
take one’s belt in (a notch)and pull one’s belt in (a notch)
tv. to prepare for lean times; to reduce expenditures. (see also tighten one’s belt.) It was clear that we would have to bite the bullet and take our belt in a notch. I gotta pull in my belt or get a second job.