St James Music Press is not free, but it is CHEAP and could give you a bunch of options. Another option (also not free) is The Oxford Book of Easy Flexible Anthems.

There's also this free PDF scan of a collection of over 120 three-voice short Latin motets for SSA.

https://archive.ccwatershed.org/media/pdfs/13/07/17/15-29-38_0.pdf

I highly recommend Ravanello.

Are you looking for anything in particular? I have a lot of SSA/ SA music that I could send you. Its all we sing here.

If you have an organ, historically, music of many parts was sung and the missing parts played by instruments, the organ being the most like the human voice, it can blend very well when it plays just the missing parts.

At www.sacredmusiclibrary.com/essentials we have a large book and two smaller books that are taken from the larger book, lighter and easier to hold.

All three books have full accompaniments.
All three are free to download if you cannot afford music in your parish.

Best Wishes, Cheryl!

Actually, Multi-Category Search also has specific voicings. One has to click on the tiny little box to the left of the checkbox for "3 part choral music" to expand that category to all the 3-part subcategories ... then check, say, the SSA box for SSA music.

There is also another template: On CPDL, using the template "MultiCatList" ... for example:

{{MultiCatList|Sacred music|Works in English|SSA}}

produces the output (the work titles are displayed as links to the CPDL work pages):

There are 55 pages common to the categories Sacred music, Works in English, and SSA.

Up to 500 results, starting with result 1 ... (500):

'Til the morning star shall rise (Nichola Hawkins)
3 canoni a 3 voci (Giovanni Bataloni)
A heritage of hope and a legacy of love (Sally DeFord)
Anglican Chant a 3 (Christoph Dalitz)
Ascendit Deus (Christoph Dalitz)
At eventide it shall be light (Alfred Robert Gaul)
At the stations of the Cross (Christopher Upton)
Bakerwoman God (Tim Blickhan)
Come unto Christ (Sally DeFord)
Come, ye blessed of my Father (Crys Armbrust)
Create in me a clean heart (Allan Loucks)
Deep River (Hugh S. Roberton)
Elias 28 Lift thine eyes / Hebe deine Augen (Felix Mendelssohn)
Father in Heaven (Friedrich Ferdinand Flemming)
Gabriel's greeting (Douglas Brooks-Davies)
God rest you merry, gentlemen (Traditional)
Hosanna! (David Greenwood)
I Sing of a Maiden (Peter Smith)
I saw the soul (Carlotta Ferrari)
Into this world of sorrow (Clifford Boyd)
Jesus, Thou Joy of loving hearts (Ronald McVey)
Little Lamb (George Whitefield Chadwick)
Magnificat (Philip Le Bas)
Magnificat alternatim trium vocum (Christoph Dalitz)
Magnificat and Nunc dimittis, 3 Faux Bourdon Settings (Denis Mason)
Magnificat peregrini toni (Christoph Dalitz)
Mary sings a lullaby (Leanne Daharja Veitch)
My sister's hands (Sally DeFord)
Nunc Dimittis (Philip Le Bas)
O wondrous God who made this world (Ronald McVey)
Peace I leave with you (John Varley Roberts)
Preces and Responses (SSA) (William Armiger)
Psalm 23 (Tim Brace)
Quiet Prayer (Philip Le Bas)
Rejoice ye with Jerusalem (Walter Spinney)
Saint Anne's Lullaby (Michelle Mitsui)
Schönster Herr Jesu / Fairest Lord Jesus (Christoph Dalitz)
Sing ye to the Lord (Charles H. Giffen)
The Aaronic Blessing (Christoph Dalitz)
The Christ-Child (Philip Le Bas)
The Good Old Way (Peter Foggitt)
The Lamb (Tim Blickhan)
The Trinity (Carlotta Ferrari)
The earth is the Lord's (Ernest Walker)
There is a balm in Gilead (Traditional)
There is no rose a 3 (David Greenwood)
This is my Father's world (Ronald McVey)
Three Evening Contemplations (William Armiger)
Un flambeau, Jeannette, Isabelle (Nicolas Saboly)
Vexilla regis (Christoph Dalitz)
Watt's Cradle Carol (Philip Le Bas)
Wayfaring Stranger (Traditional)
We heard a baby crying (Philip Le Bas)
What sweeter music (David Greenwood)
When Mary sang her lullaby (Sally DeFord)

You're being asked to square the circle here, due to a V2 hermeneutic of rupture. There is a ton of 2-3 part equal voice music that is at least serviceable and often great, and out of copyright. It's in Latin. There is a fair bit (but less) of music in English for this combination; it's mostly under copyright. This is particularly problematic when we seek to sing the liturgical texts (as we should) and need them to be the correct translation. I'm not saying that what you want to do can't be done, but it can't be done well or easily. Of course your paycheck shouldn't need to go for buying basic choral supplies (and that assumes that you're actually paid.) But it may be actually easier to raise money than it is to find the small amount of free music that suits your requirements. And I say this as a guy who hates raising money and is not good at it. Ideally, the choir should be an item in the church budget, but if not, you'll have to beg, bake sale, or whatever. That you are in this situation is the work of your bishop, priest, or uncatechised people ( = ultimately the priest). It's probably not helpful to point out which of these it actually is. But in the event you receive pushback. you'll need to point out that, generally, free music isn't English, and English music isn't free, and if we want to Sing A New Church Into Being, it's going to cost.