This generally depends on the bank's specific policy, since some allow a supplementary cardholder's purchase to be converted to EMI directly, while others require the primary cardholder to initiate or approve the conversion given that ultimate liability for the account rests with them. In either case, the resulting EMI plan and its balance are typically counted against the shared account's overall credit limit and remain the primary cardholder's legal responsibility, regardless of which cardholder made the original purchase.
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