Explain a TRC-10 transfer that lost issuer Bandwidth sponsorship

TRC-10 issuer sponsorship uses three independent limits. A sender with ample personal token allowance can still pay the transaction’s Bandwidth when the shared token allowance is nearly spent.

Test the complete byte charge against each quota

For a transfer from a non-issuer to an activated account, check the sender’s unused sponsorship for this token, the token-wide unused sponsorship and the issuer’s available staked or delegated Bandwidth. Each must cover the whole transaction. The example isolates the shared quota as the limiting factor.

byte_cost = 280
holder_allowance = 400
shared_allowance = 270
issuer_bandwidth = 1000
assert min(holder_allowance, shared_allowance, issuer_bandwidth) < byte_cost

Identify who paid the fallback

A 280-unit charge exceeds the shared quota of 270. The ordinary sender-side Bandwidth rules then apply, so the sender may consume its own resources or burn TRX. For an unactivated destination, inspect account-creation charging rules instead. Record token ID and recipient activation state with the receipt when comparing two apparently identical transfers.

Sources