Financial Liabilities - Maturity Analysis of Financial Liabilities (Details) - EUR (€) € in Millions	Dec. 31, 2024	Dec. 31, 2023
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Loans and other payables	€ 4,014	€ 3,601
Telefónica, S.A.
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Debentures and bonds	31,255
Promissory notes & commercial paper	1,449
Total Issues	32,704
Loans and other payables	4,014
Derivative instruments (Note 19)	2,064
Total	38,782	€ 37,061
Telefónica, S.A. \| Less than 1 year
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Debentures and bonds	3,559
Promissory notes & commercial paper	1,276
Total Issues	4,835
Loans and other payables	556
Derivative instruments (Note 19)	199
Total	5,590
Telefónica, S.A. \| 2026
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Debentures and bonds	2,046
Promissory notes & commercial paper	12
Total Issues	2,058
Loans and other payables	389
Derivative instruments (Note 19)	160
Total	2,607
Telefónica, S.A. \| 2027
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Debentures and bonds	4,019
Promissory notes & commercial paper	3
Total Issues	4,022
Loans and other payables	643
Derivative instruments (Note 19)	562
Total	5,227
Telefónica, S.A. \| 2028
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Debentures and bonds	2,006
Promissory notes & commercial paper	19
Total Issues	2,025
Loans and other payables	277
Derivative instruments (Note 19)	376
Total	2,678
Telefónica, S.A. \| 2029
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Debentures and bonds	2,422
Promissory notes & commercial paper	10
Total Issues	2,432
Loans and other payables	565
Derivative instruments (Note 19)	283
Total	3,280
Telefónica, S.A. \| Subsequent years
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Debentures and bonds	17,203
Promissory notes & commercial paper	129
Total Issues	17,332
Loans and other payables	1,584
Derivative instruments (Note 19)	484
Total	19,400
Telefónica, S.A. \| Non-current total
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Debentures and bonds	27,696
Promissory notes & commercial paper	173
Total Issues	27,869
Loans and other payables	3,458
Derivative instruments (Note 19)	1,865
Total	€ 33,192

The amount of contractual undiscounted cash flows in relation to bank borrowings. [Refer: Borrowings]

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-Name IFRS
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The amount of contractual undiscounted cash flows in relation to bonds issued. [Refer: Bonds issued]

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The amount of outstanding funds that the entity is obligated to repay.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
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The amount of contractual undiscounted cash flows in relation to derivative financial liabilities. [Refer: Derivative financial liabilities]

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
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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.

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No definition available.

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The amount of liabilities that are: (a) a contractual obligation: (i) to deliver cash or another financial asset to another entity; or (ii) to exchange financial assets or financial liabilities with another entity under conditions that are potentially unfavourable to the entity; or (b) a contract that will, or may be, settled in the entity’s own equity instruments and is: (i) a non-derivative for which the entity is, or may be, obliged to deliver a variable number of the entity’s own equity instruments; or (ii) a derivative that will, or may be, settled other than by the exchange of a fixed amount of cash or another financial asset for a fixed number of the entity’s own equity instruments. For this purpose, rights, options or warrants to acquire a fixed number of the entity’s own equity instruments for a fixed amount of any currency are equity instruments if the entity offers the rights, options or warrants pro rata to all of its existing owners of the same class of its own non-derivative equity instruments. Also, for those purposes the entity’s own equity instruments do not include puttable financial instruments that are classified as equity instruments in accordance with paragraphs 16A-16B of IAS 32, instruments that impose on the entity an obligation to deliver to another party a pro rata share of the net assets of the entity only on liquidation and are classified as equity instruments in accordance with paragraphs 16C-16D of IAS 32, or instruments that are contracts for the future receipt or delivery of the entity’s own equity instruments. As an exception, an instrument that meets the definition of a financial liability is classified as an equity instrument if it has all the features and meets the conditions in paragraphs 16A-16B or paragraphs 16C-16D of IAS 32. [Refer: Classes of financial instruments [domain]; Financial assets; Derivatives [member]]

+ References

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The amount of contractual undiscounted cash flows in relation to trade and other payables. [Refer: Trade and other payables]

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