Major credit card issuers on Tuesday posted improved results for May, in another sign consumers are getting a handle in paying back their debts.

The rate of payments that were 30 days or more past due fell for all six of the biggest card companies, with Citigroup Inc. posting the biggest improvement. Citi said its delinquency rate dropped to 8.42 percent in May from 9.02 percent in April. Bank of America, JPMorgan Chase, American Express, Capital One and Discover all posted delinquency rate improvements of at least 0.2 percentage points.

Delinquency rates have been steadily improving for five months, indicating that consumers have gotten control of their debt payments even as the unemployment rate has remained high.

Most observers attribute the improvements to consumers paring back spending and focusing on paying down debt. Federal Reserve statistics show that total credit card debt was down about 12.5 percent since peaking in mid-2008, to $838 billion in April.

But a good portion of that drop — some estimate two-thirds or more, but certainly billions of dollars — came from charge-offs, or balances written off as uncollectable.

Some analysts also suggest that consumers are benefiting from the credit card regulations that took effect in February. By constraining the ability of banks to raise interest rates and limiting fees, the rules made it easier for cash-strapped consumers to keep up with their payments, these analysts say.

For May, five of the six companies reported lower charge-off rates.

Only Discover reported an increase in the amount it wrote down, reversing the recent trend for the Riverwoods, Ill., company.