







Using transaction data from a US consumer payments diary, we revisit the credit card debt puzzle—a scenario in which households revolve credit card debt while also keeping liquid assets as bank account deposits. This scenario is very common: 42 percent of consumers in our sample were borrower-savers in 2019. We explain the puzzle by showing that consumers need their liquid assets to pay household bills and other necessary expenses, including mortgage or rent. More than 80 percent of bills by value were paid out of bank accounts and could not be charged to credit cards, so bank account balances were needed to cover those basic expenses. On average, borrower-savers’ credit card debt exceeded their liquid assets. The average borrower-saver carried almost $6,400 in unpaid credit card debt and had $5,400 in liquid assets. On average, the value of their liquid assets could cover only about 60 percent of their unpaid debt plus monthly bills. In almost every category of assets or debts, borrower-savers were worse off financially than savers. Thus, the differences between borrower-savers and savers are much broader than just their credit card debt and bank account balances; they extend to mortgage debt and home equity. Carrying a mortgage or other debt (such as auto or educational loans) is associated with a higher probability of revolving on a credit card, suggesting that various types of household debt might be complements rather than substitutes. We do not find evidence that either financial literacy scores or the “Big 5” personality traits predict whether a consumer is a borrower-saver. During the COVID-19 pandemic in 2020, bor-savs’ behavior was consistent with what we would expect under our explanation for the credit card puzzle. However, consumers’ unpaid credit card debt decreased, and their liquid assets increased, so the fraction of borrower-savers dropped to 35 percent of the sample.
Household Need for Liquidity and the Credit Card Debt Puzzle
Abstract. In the 2001 U.S. Survey of Consumer Finances, 27% of households report simultaneously revolving significant credit card debt and holding sizeable

The Credit Card Debt Puzzle: The Role of Preferences, Credit Access Risk, and Financial Literacy
Abstract. We use the 1979 National Longitudinal Survey of Youth to revisit what is termed the credit card debt puzzle: why consumers simultaneously co-hold high-interest credit card debt and low-interest assets that could be used to pay down this debt. Relative to individuals with no credit card debt but positive liquid assets, borrower-savers have very different perceptions of future credit access risk and use credit cards for precautionary motives. Moreover, changing perceptions about credit access risk are essential for predicting transitions among the two groups. Preferences and the composition of financial portfolios also play a role in these transitions.

Disclosing the costs of co-holding liquid assets and high-interest debt has limited impact on behavior
Abstract Why do consumers simultaneously maintain low-yield liquid assets and high-interest revolving debt? This behavior, known as ``co-holding,'' affects 23\% of credit card users in our sample from a major international bank and costs the typical co-holder hundreds of dollars annually in unnecessary interest charges. Our analysis of 38 months of detailed banking records reveals that co-holding is remarkably persistent, with typical co-holders maintaining this behavior for most months observed. Our analysis also reveals that co-holding is not a static financial position: co-holders regularly deposit and withdraw from asset accounts while simultaneously making new credit card purchases. To test whether co-holding could be addressed through information disclosure, we conducted a large-scale field experiment (n = 125,328), providing clear information about co-holding behavior and its costs. Customers received targeted messages through their bank's mobile app, where they could easily transfer money from assets to pay down debt. Despite sufficient power to detect economically small effects, we found no meaningful changes in debt repayment amount, though customers did respond in other ways---making more frequent repayments and paying above required minimums. These results challenge explanations based on limited attention or information gaps and suggest that simple information disclosure, even when carefully designed and delivered through trusted channels, may not effectively address costly financial behaviors.

Overconfidence and the Credit Card Debt Puzzle
This article investigates the credit card debt puzzle. Simultaneously holding credit card debt and liquid assets is puzzling given the sizeable difference between interest rates of debt and assets. However, this behavior is common—about 31% of households in the 2016 Survey of Consumer Finances. The cost of co-holding may be justified if consumers anticipate future restrictions in credit or if they need to maintain liquidity. Other existing explanations for co-holding include impulsive spending and low financial literacy. This research reveals a new explanation for the credit card debt puzzle: consumers’ overconfidence of their financial knowledge. Using a Coarsened Exact Matching method, we found that overconfident consumers were 20%–40% more likely to co-hold credit card debt and liquid assets.
The Credit Card Debt Puzzle and Noncognitive Ability
Abstract Many households concurrently hold low-yield liquid assets while incurring costly credit card debt. In our sample, more than 80% of households with credit card debt also have low-yield liquid assets. Using data from the Health and Retirement Study (N = 30,517), we examine the role of noncognitive skills as well as the economic, financial, and demographic factors that affect the likelihood of co-holding. We find that the “Big Five” personality traits have a statistically significant and economically important effect: households with a more agreeable, introvert, and less conscientious head of household are more likely to co-hold. We also examine the role of intra-household dynamics.

Credit Card Debt Puzzle: Liquid Assets to Pay Bills
Using transaction data from a US consumer payments diary, we revisit the credit card debt puzzle—a scenario in which consumers revolve credit card debt while al
The Co-Holding Puzzle: New Evidence from Transaction-Level Data
The tendency of consumers to hold low-yield liquid savings while simultaneously holding high-cost unsecured credit on revolving credit lines is a long standing
Cash versus Debit Card: The Role of Budget Control
Due to the financial crisis, an increasing number of households face financial problems. This may lead to an increasing need for monitoring spending and budgets. We demonstrate that both cash and the debit card are perceived as helpful in this respect. We show that, on average, consumers responsible for financial decision making within a household find cash and the debit card equally helpful for monitoring their household finances. Individuals differ in major respects, however. In particular, low earners and the liquidity‐constrained prefer cash as a budgeting tool. Finally, we present evidence that at an aggregated level, such preferences strongly affect consumer payment behavior. These findings suggest that the substitution of cash by cards may slow down because of the financial crisis.

Timing to the Statement: Understanding Fluctuations in Consumer Credit Use
We show that consumers spend 15% more per day in the first week following the receipt of a credit card statement than in the days just prior to the statement. This increase in spending includes both an increase in the likelihood that they use the credit card in the first weeks following their statement and an increase in transaction amount on days they use the credit card. In contrast to the effect on credit card spending, debit card spending is unaffected by credit card statement issuance, suggesting that consumers are not simply switching among modes of payment. Our estimates are based on exogenous variation from bank-assigned statement dates. We propose and test several alternative explanations to this spending puzzle: optimization of the free float, salience effect of the credit card statement, mental accounting, liquidity constraints, and automatic payments. We find that the consumers most apt to spend early in the credit card cycle tend to be those who do not revolve balances and are not close to their credit limit. Thus, this paper documents a puzzle with mixed support for several alternative explanations. This paper was accepted by David Simchi-Levi, finance.

Keeping Cash and Revolving Debt: How Consumers' Preference for Spending on Debit versus Credit Influences their Decision to Co-Hold
This paper investigates "co-holding'"–whereby consumers simultaneously maintain low-yield liquid assets and high-interest revolving debt–through the l
Do Liquidity Constraints and Interest Rates Matter for Consumer Behavior? Evidence from Credit Card Data
Abstract. This paper utilizes a unique data set of credit card accounts to analyze how people respond to credit supply. Increases in credit limits generate

Does Saving Cause Borrowing? Implications for the Co-Holding Puzzle
Using an experiment in which 3.1 million bank customers were encouraged to save, we explore the mechanisms behind co-holding liquid savings and credit card debt. Theoretically, we first show that the joint responses of spending, saving, and borrowing to the nudge differ for different economic models of co-holding. Using machine learning techniques, we then find that the most responsive individuals reduce spending and increase their savings by 4.9% (206 USD PPP per month) while their credit card debt remains unchanged. For them, the marginal responses to the nudge are consistent with our model of co-holding for the purpose of self- or partner control.

Does Saving Cause Borrowing? Implications for the Coholding Puzzle
ABSTRACT Using an experiment in which 3.1 million bank customers were encouraged to save, we explore the mechanisms behind coholding liquid savings and credit card debt. Theoretically, we show that the joint responses of spending, saving, and borrowing to the nudge differ across economic models of coholding. Using machine learning techniques, we find that the most responsive individuals reduce spending and increase savings by 4.9% (206 USD PPP per month) while their credit card debt remains unchanged. These individuals' marginal responses to the nudge are consistent with our model of coholding for the purpose of self‐ or partner‐control.

Consumer Rationality and Credit Cards
Borrowing on credit cards at high interest rates might appear irrational. However, even low transactions costs can make credit cards attractive relative to bank loans. Credit cards also provide liquidity services by allowing consumers to avoid some of the opportunity costs of holding money. The effect of alternative interest rates on the demand for card debits can explain why credit card interest rates only partially reflect changes in the cost of funds. Credit card interest rates that are inflexible relative to the cost of funds are not inconsistent with a competitive equilibrium that yields zero profits for the marginal entrant.
Credit Card Debt Puzzles and Debt Revolvers for Self Control
Abstract Most US credit card holders revolve high-interest debt, often with substantial liquid and retirement assets. We model separation of accounting from shopping allowed by credit cards, in a rational, dynamic game. When the shopper is more impatient than the accountant, selling assets to repay debt is not necessarily optimal, as the shopper can restore debt. Modest relative impatience generates asset-debt co-existence and target utilization rates, matching incidence and median assets of debt revolvers with substantial assets. Empirical evidence is consistent with a role for spending control considerations, after allowing for standard determinants of credit card debt.

Consumption Response to Credit Expansions: Evidence from Experimental Assignment of 45,307 Credit Lines
In a field experiment that constructs a randomized credit limit shock, participants borrow to spend 11 cents on the dollar in the first quarter and 28 cents by the third year. Effects extend to those far from the limit, those who had the new limits as available credit, and those with a liquid asset buffer. In the short-run, flexible and installment contracts are used in tandem, with unconstrained using installments more. Long-run borrowing is predominantly using installments. Near limits, participants borrow when credit expands but save out of constraints when limits are tight. Findings support a buffer-stock interpretation emphasizing precautionary saving.