XML 435 R353.htm IDEA: XBRL DOCUMENT
v3.26.1

Risk management - Schedule of maturity analysis of assets and guarantees received and committed (Details) - Liquidity risk - With mortgage collateral € in Millions | Dec. 31, 2025 EUR (€)
--- | ---
On-balance-sheet assets |
Disclosure of reconciliation of changes in loss allowance and explanation of changes in gross carrying amount for financial instruments [line items] |
Committed assets | € 306,400
On-balance-sheet assets | Unmatured |
Disclosure of reconciliation of changes in loss allowance and explanation of changes in gross carrying amount for financial instruments [line items] |
Committed assets | 24,200
On-balance-sheet assets | 1 month |
Disclosure of reconciliation of changes in loss allowance and explanation of changes in gross carrying amount for financial instruments [line items] |
Committed assets | 50,700
On-balance-sheet assets | 1 to 3 months |
Disclosure of reconciliation of changes in loss allowance and explanation of changes in gross carrying amount for financial instruments [line items] |
Committed assets | 14,100
On-balance-sheet assets | 3 to 12 months |
Disclosure of reconciliation of changes in loss allowance and explanation of changes in gross carrying amount for financial instruments [line items] |
Committed assets | 38,400
On-balance-sheet assets | 1 to 2 years |
Disclosure of reconciliation of changes in loss allowance and explanation of changes in gross carrying amount for financial instruments [line items] |
Committed assets | 38,800
On-balance-sheet assets | 2 to 3 years |
Disclosure of reconciliation of changes in loss allowance and explanation of changes in gross carrying amount for financial instruments [line items] |
Committed assets | 29,500
On-balance-sheet assets | 3 to 5 years |
Disclosure of reconciliation of changes in loss allowance and explanation of changes in gross carrying amount for financial instruments [line items] |
Committed assets | 37,700
On-balance-sheet assets | 5 to 10 years |
Disclosure of reconciliation of changes in loss allowance and explanation of changes in gross carrying amount for financial instruments [line items] |
Committed assets | 36,300
On-balance-sheet assets | More than 10 years |
Disclosure of reconciliation of changes in loss allowance and explanation of changes in gross carrying amount for financial instruments [line items] |
Committed assets | 36,600
Off-balance-sheet assets |
Disclosure of reconciliation of changes in loss allowance and explanation of changes in gross carrying amount for financial instruments [line items] |
Guarantees received committed | 185,160
Off-balance-sheet assets | Unmatured |
Disclosure of reconciliation of changes in loss allowance and explanation of changes in gross carrying amount for financial instruments [line items] |
Guarantees received committed | 2,200
Off-balance-sheet assets | 1 month |
Disclosure of reconciliation of changes in loss allowance and explanation of changes in gross carrying amount for financial instruments [line items] |
Guarantees received committed | 85,200
Off-balance-sheet assets | 1 to 3 months |
Disclosure of reconciliation of changes in loss allowance and explanation of changes in gross carrying amount for financial instruments [line items] |
Guarantees received committed | 28,200
Off-balance-sheet assets | 3 to 12 months |
Disclosure of reconciliation of changes in loss allowance and explanation of changes in gross carrying amount for financial instruments [line items] |
Guarantees received committed | 61,800
Off-balance-sheet assets | 1 to 2 years |
Disclosure of reconciliation of changes in loss allowance and explanation of changes in gross carrying amount for financial instruments [line items] |
Guarantees received committed | 4,000
Off-balance-sheet assets | 2 to 3 years |
Disclosure of reconciliation of changes in loss allowance and explanation of changes in gross carrying amount for financial instruments [line items] |
Guarantees received committed | 800
Off-balance-sheet assets | 3 to 5 years |
Disclosure of reconciliation of changes in loss allowance and explanation of changes in gross carrying amount for financial instruments [line items] |
Guarantees received committed | 1,900
Off-balance-sheet assets | 5 to 10 years |
Disclosure of reconciliation of changes in loss allowance and explanation of changes in gross carrying amount for financial instruments [line items] |
Guarantees received committed | 1,100
Off-balance-sheet assets | More than 10 years |
Disclosure of reconciliation of changes in loss allowance and explanation of changes in gross carrying amount for financial instruments [line items] |
Guarantees received committed | € 0

X
- Definition The fair value of collateral sold or repledged that was permitted to be sold or repledged in the absence of default by the owner of the collateral. [Refer: At fair value [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2025-01-01 -Paragraph 15 -Subparagraph b -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2025-en-r&anchor=para_15_b&doctype=Standard -URIDate 2025-03-27 + Details
Name: | ifrs-full_AssetsSoldOrRepledgedAsCollateralAtFairValue
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table. + References No definition available. + Details
Name: | ifrs-full_DisclosureOfReconciliationOfChangesInLossAllowanceAndExplanationOfChangesInGrossCarryingAmountForFinancialInstrumentsLineItems
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Committed Assets, Including Own Debt Securities Other Than Covered Bonds And Asset Backed Securities + References No definition available. + Details
Name: | san_CommittedAssetsIncludingOwnDebtSecuritiesOtherThanCoveredBondsAndAssetBackedSecurities
Namespace Prefix: | san_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | ifrs-full_TypesOfRisksAxis=ifrs-full_LiquidityRiskMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | san_TypesOfAssetsAxis=san_OnBalanceSheetAssetsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | san_Collateral1Axis=san_IFRSCollateralPledgedMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=san_UnmaturedMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=ifrs-full_NotLaterThanOneMonthMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=ifrs-full_LaterThanOneMonthAndNotLaterThanThreeMonthsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=ifrs-full_LaterThanThreeMonthsAndNotLaterThanOneYearMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=ifrs-full_LaterThanOneYearAndNotLaterThanTwoYearsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=ifrs-full_LaterThanTwoYearsAndNotLaterThanThreeYearsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=ifrs-full_LaterThanThreeYearsAndNotLaterThanFiveYearsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=ifrs-full_LaterThanFiveYearsAndNotLaterThanTenYearsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=ifrs-full_LaterThanTenYearsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | san_TypesOfAssetsAxis=san_OffBalanceSheetAssetsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |