The Mexican Institute of Social Security (IMSS) acted ethically and under an agreement signed in May 2020 between the IMSS Directorate and the General Secretary of its Union.
The promise: any Mexican could be treated at IMSS, ISSSTE, or IMSS-Bienestar, and a "compensation box" would balance the books between institutions. If an ISSSTE beneficiary was treated at IMSS, the latter would charge them for the service and vice versa.
Does this sound familiar? What IMSS did was right. To publish the complete balance of the COVID experience at IMSS. It also changed, without most people fully noticing, the way our health system functions and is financed. That is not up for debate.
What does deserve analysis is why, once the emergency was over, the state never compensated the Institute for the economic resources it expended in the medical care of non-beneficiaries. The 2020 agreement promised that IMSS would request the "compensation of the costs incurred." The payment never arrived.
COVID care for non-beneficiaries, without anyone having planned it, was the trial run, or pilot, of health service portability in Mexico. Opening the doors to those who came asking for help, without asking if they had a credential, was an act of institutional humanity that saved thousands of Mexicans.
Yes, six years after the pandemic began, this speaks to a weakness in the data capture systems. The fact that should keep more than one person awake is: what happened with that charge? This is what happened during the pandemic. All of that, in an invoice that no one has paid.
Now comes what matters today. And to design with that data a financial mechanism that truly works for the "Universal Health System." And what we learned from that experience—or rather, what we decided not to learn—is about to become much more important than it seems.
During the pandemic, IMSS treated people who were not its beneficiaries. However, estimates based on the IMSS's own unitary costs and documented care volumes, as well as official internal records from the institution itself, place the debt at between three and five billion pesos. To date, there is no public evidence that the federal government has formally reimbursed IMSS for the specific cost of treating these patients.
The problem lies in the financial engineering behind it. Because those who financed that solidarity with their dues are also mothers, fathers, and workers who depend on IMSS to care for their own health. The official IMSS communication from April 2025 speaks of 353,000 people without social security treated during the pandemic. This is, in essence, a silent transfer of debt to the formal employment sector, eroding the financial reserve that should guarantee the health of those who do contribute to the system.
And how much is the unrecovered amount? There is no official public document from IMSS that reports the exact, broken-down figure. To put the figure into perspective, the uncollected amount is equivalent to the budgetary increase that this year, together, the country's fourteen national health institutes received.
The virus since then changed everything. Because the pilot test has already been done. And the results are eloquent: incomplete records, validation that takes years, a charge that is not concretized, and IMSS left with the bill. A system where any person receives medical care without bureaucratic barriers is a correct and necessary goal.
To say how much it cost, how much was recovered, and how much was lost. Without standardized fees, without compatible computer systems between institutions, without real reconciliation deadlines, and above all, without an explicit source of financing for those who do not contribute to any system, the compensation box runs the risk of becoming a box of accumulated debts, just as happened during the pandemic.
Before activating financial flows between institutions, the government can do something it did not do with the pandemic: evaluate. Here the story becomes uncomfortable. From neither INSABI, nor the Ministry of Finance, nor the Health Fund for Well-being (Fonsabi). The IMSS's own financial reports confirm that the expenditure was covered "with charge to the authorized budget, through the reorientation of resources." Translation: the dues of workers and employers paid the bill for those who did not have insurance.
On April 2, the credentialing for the Universal Health Service begins. Six years ago, at the end of March 2020, Mexican authorities issued the emergency declaration due to the COVID-19 virus. All that's missing is for someone to review it. But internal documents from the institution tell another story.
No life has a price, and no cost justifies denying care to a person in a serious health situation that could end their life. The records captured speak of around 236,000 records validated by the Institute's medical and financial areas to proceed with the recovery of the costs incurred.
