Planning on having all bills due on the same day

I currently have 3 credit cards, one of which I virtually never use.I'm planning on calling the companies and asking to change the billingcycle so they end on the last day of each month. This would line upwith my rent so I can pay everything at once.

In my experience most companies are flexible regarding the end of the billing cycle, and the resulting due dates.

The ones that weren't flexible were utilities that required a person or device to read the usage. This could be gas, electricity, or water. They wanted to read everybody in the neighborhood on the same day. As we move towards smart meters this requirement may go away.

You may find that you don't want the billing cycle to be at the end of the month, you want the due date to be early in the month so that you can send in all the payments at the same time. Most companies have a several week grace period between the end of the cycle and the due date. If the cycle ends at the last day of the month you may find that the bill isn't generated until a few days later.

Some bills you may know exactly what the bill will be. In other cases you won't know. Utilities vary by month. So do other bills such as your credit cards.

Is my reasoning sound? Is there any downside? Now that I think of it,why do so many bills fall on random days of the month. Why isn't itcommon (like with leases) that payment is due on the first or last dayof the month?

If you are paid once a month or twice a month then the timing of the bill during the month can allow you to get into a rhythm. But if you are paid every two weeks that rhythm with monthly bills doesn't last.

Why do companies spread the due dates out? It allows them to get money throughout the month. They also have expenses and getting all income on one day gives them money management problems.

I want to cycle back to an earlier statement:

asking to change the billing cycle so they end on the last day of each month.

While many companies will be flexible, that doesn't mean that all dates are possible. They might not make the end of the cycle or the due date be the last day of the month because that could be the 28th, 29th, 30th, or 31st depending on the month. They also have to factor in weekends and holidays. What do they due if the key date falls on a Sunday, they might not want to send the meter reader out on a weekend.

Most people who care when a bill falls during the month are living paycheck-to-paycheck and want their bills that have due dates that match up to their paychecks. Having all their bills due at the end of the month would be catastrophic for those folks because that would wipe out their entire paycheck and leave them nothing for, say, groceries until their next paycheck came in. Most credit cards in my experience default to a due date somewhere in the middle of the month so that they're offset from housing expenses for just this reason. Since you're asking the question, I assume you're not part of this group.

Personally, I have basically everything set up to autopay-- either via my bank's bill pay, by automatically charging my credit card, or by debiting my bank account-- so I don't have to worry about doing something with bills on a particular day every month. If you prefer to keep some sort of human step in your billing process, having everything due at once seems reasonable. Depending on when your cards report your balance to the credit buraus, you might see a small change in your credit score based on having a slightly higher or lower balance on the reporting date if you move the billing date. For most people, that's a minor change they should ignore but it may be something you care about if you're close to a credit score cut-off or if you're using a large fraction of your available credit every month.

Is my reasoning sound? Is there any downside?

If you prefer it and can orchestrate it with your bills then go for it, I can't think of any downside.

Why isn't it common (like with leases) that payment is due on thefirst or last day of the month?

Many monthly services aren't started on the first of the month. Services that you pay a variable amount based on usage usually have a delay between the end of the billing period and the due-date to give companies time to collect usage data and/or ensure its accuracy. Additionally, the prevalence of auto-pay likely means there is not a huge demand for synchronized billing.