Waste not, want not
If we don't waste what we have, we'll still have it in the future and will not lack (want) it.
The New Dictionary of Cultural Literacy, Third Edition
Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Idioms and Phrases with waste not, want not
waste not, want not
Wise use of one's resources will keep one from poverty. For example, I just hate to throw out good food—waste not, want not. This proverbial saying was first recorded in 1772 but had an earlier, even more alliterative version, willful waste makes woeful want (1576).
The American Heritage® Idioms Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.