Mexico 100 Pesos Sor Juana (Series G, 2020): Value & Guide

If you have a red Mexican 100-peso note showing a woman on the front and butterflies on the back, here is the honest answer: in 2026 it is worth its face value, about 5 to 6 US dollars, because it is current circulating money. The exceptions that trade for more are printing errors, low or radar serial numbers, and crisp uncirculated notes from the first print runs. Those can bring several times face.

This is the 100-peso note of Series G (in Spanish, familia G), the current generation of Mexican banknotes issued by Banco de México, the country's central bank. It entered circulation on November 12, 2020. "Series G" is simply the letter Mexico uses to label this design family, the way collectors track note generations.

What it's worth in 2026

A standard circulated example is worth exactly its face value: 100 pesos, roughly 5 to 6 US dollars depending on the exchange rate. There is no collector premium on a common, worn note from a current series, and any English-language site telling you otherwise is chasing clicks.

What actually adds value:

1. Printing errors. Misaligned cuts, ink smears, factory folds, missing print, or off-center serials turn an ordinary note into a genuine rarity worth several times face, sometimes into the tens or low hundreds of US dollars for a dramatic, authenticated error. Normal wear and use damage is not an error.
2. Low or radar serial numbers. A very low serial (like 0000015) or a radar/palindrome serial (reads the same forward and backward) draws collector interest.
3. Uncirculated first-run notes. A crisp, unhandled note graded 65 or higher by PMG (the main third-party grading service for world paper money) from the earliest print runs is the piece that gains value over the coming years. Series G is still young, so it has not yet produced the scarce, retired-series rarities that older Mexican families have.

Note	Series	Condition	Approx. value (USD)
100 pesos Sor Juana	G (2020)	Circulated, common	Face value (about 5 to 6)
100 pesos Sor Juana	G (2020)	Uncirculated, first runs	Small premium over face
100 pesos Sor Juana	G (2020)	Low / radar serial	Several times face
100 pesos Sor Juana	G (2020)	Genuine printing error	10 to 100+, error-dependent

The note itself

The front carries the portrait of Sor Juana Inés de la Cruz, the 17th-century poet, scholar and nun, one of the great figures of colonial-era literature in the Spanish-speaking world. Beside her portrait is a view of the main courtyard of the Antiguo Colegio de San Ildefonso, a landmark colonial school building in the historic center of Mexico City.

The back is dedicated to the temperate forest: the pine, oak and fir (oyamel) woodland of the Monarch Butterfly Biosphere Reserve, straddling the states of México and Michoacán. This is where millions of monarch butterflies overwinter after migrating from Canada, and it is a UNESCO World Heritage Site. The note is printed on polymer (a plastic substrate), not paper, which is why it feels smoother and more durable than older Mexican bills.

How to tell if it's genuine

Check the security features by hand and against the light:

• Transparent window: the polymer has a clear see-through area, extremely hard to fake.
• Watermark and shadow images visible when held to the light.
• Security thread embedded in the substrate.
• Raised printing (intaglio): you should feel texture under your fingers on the portrait and main elements.
• Microprinting that stays sharp under magnification.

A counterfeit usually feels flat and smooth, with no raised relief, and a watermark that is printed on rather than built into the substrate. If you are unsure, post clear photos of both sides in the Pesoteca forum and the community will help you verify it.

Where to sell it

If you have a standard note, a bank will simply exchange it at face value. For anything with a possible error, special serial, or uncirculated condition, the collector market pays better:

• A verified numismatic dealer from the Pesoteca directory can appraise it on the spot.
• The Pesoteca buy-and-sell forum connects you with collectors directly.

Photograph both sides in good light, note the serial number, and check for low or radar serials and any factory error before you accept an offer. Do not dump it on a social-media marketplace to the first bidder.

Have one with an unusual serial or a possible printing error? Post it in the forum and let the community weigh in. If you are researching the previous generation, see the Series F banknotes.

A 100-peso note from Family G, the series of Mexican banknotes currently in circulation (starting in 2018), printed on polymer and with a vertical orientation on its main side. Banco de México conceived this generation to link the country's great historical processes with its protected ecosystems.

The obverse is dedicated to the colonial era through Sor Juana Inés de la Cruz, the greatest poet and thinker of New Spain, the 'Tenth Muse', a pioneering figure in the defense of women's learning. She is accompanied by a fragment of the main courtyard of the Antiguo Colegio de San Ildefonso, in the Historic Center of Mexico City. The reverse presents the temperate forest of pine, oak, and fir of the Monarch Butterfly Biosphere Reserve, between the State of Mexico and Michoacán, where each winter millions of butterflies gather.

This piece sums up the spirit of Family G: a historical figure of cultural weight on one side and an emblematic ecosystem on the other. The combination of Sor Juana and the monarch butterfly has made it one of the most celebrated notes of contemporary Mexican design.

An award-winning note worldwide

The 100-peso note, the one with Sor Juana Inés de la Cruz, is also award-winning: Banknote of the Year 2020 from the International Bank Note Society (IBNS) and Best New Banknote of Latin America 2022. The Mexican Tenth Muse placed on the most-used note in the country, and recognized by the world.