Count interruptions as well as hands-on time
During an ordinary week, note a few duties that cannot happen whenever the owner chooses. A provider call may require thirty minutes on hold between nine and five. Folding laundry may take the same half hour but fit around an evening at home. Someone who repeatedly stops paid work to answer calls experiences a different burden even if the totals on a chore chart look equal.
Use a small swap to learn what fits
Choose a week and list which duties interrupt work, require travel, or need repeated follow-up. Swap one duty and compare how the week felt. If one person cannot make daytime calls, they can own preparing documents or evening work that removes a different burden.
Separate access constraints from differences in preference
One person may be the named account holder and have to make the call. The other can still obtain the bill, identify the disputed line, list suitable callback times and own the follow-up. Ask whether taking on that preparation actually reduced interruption for the caller. If it did not, try another exchange such as covering dinner on call days. The purpose is to make both schedules workable, not to equate every minute on paper.