Maybe it's a shoebox of baby shower cards. Maybe it's a drawer holding the ultrasound strip, the hospital bracelet, a newspaper birth announcement and the first drawing that came home from daycare. Either way, you want it to still look like this when your child is grown.

Archival storage for keepsakes sounds like museum work, but the museum version comes down to a few plain rules. Keep acid away from the paper, keep light and damp out, and don't let anything harmful touch it. Below you'll find what actually damages paper, how to read the labels, a buy-this, avoid-this materials list, and a step-by-step way to box everything up in an afternoon.

What actually damages paper keepsakes?

In short: acid, light, heat and humidity, pests, and the wrong materials touching it. Archival storage handles all five at once.

• Acid. Newsprint, construction paper and most cardboard are made from wood pulp that still contains lignin. As lignin breaks down, the paper turns acidic, yellows and gets brittle. Acid also travels, so a newspaper clipping can leave a brown shadow on the card stored against it.
• Light. Daylight and bright indoor light fade ink, photos and colored paper, and they yellow white paper. Light damage adds up over time and can't be reversed.
• Heat and humidity. Heat speeds up aging. Damp air invites mold and bugs. Swings between hot, humid summers and dry, heated winters make paper swell and shrink until it warps.
• Pests. Silverfish, cockroaches and mice eat paper, glue and paste. They like dark, damp, quiet places, which is why basements and garages are risky.
• What touches it. Rubber bands, paper clips, tape, glue and cheap plastic all break down and take the paper with them. This is the part you control completely.

A closed archival box in the right closet covers most of that list. Safe materials stop the chemical damage. The lid blocks light and dust and slows pests down. A room you keep comfortable for yourself keeps temperature and humidity steady.

What do "acid-free," "lignin-free" and "archival" actually mean?

In short: "archival" on its own is a marketing word. Look for acid-free and lignin-free, then choose buffered or unbuffered based on what you're storing.

• Acid-free: The paper had a pH of 7 or higher when it was made. That's a good start, but paper that still contains lignin can turn acidic later.
• Lignin-free: The lignin has been removed. This is what keeps acid-free paper acid-free over the long haul.
• Buffered: Contains an alkaline reserve, usually calcium carbonate, that soaks up acid over time. It's the best pick for most paper: letters, cards, certificates, children's drawings and newspaper clippings.
• Unbuffered: Neutral, with no alkaline reserve. It's the safer pick for photographs, especially color prints, and for anything with silk or wool attached. When a box holds a mix, unbuffered tissue is a safe all-rounder.
• PAT (Photographic Activity Test): A lab test that checks whether a storage material will react with photographs. If you're storing prints, "passes the PAT" on the label is what you want.
• "Archival," "photo safe," "museum quality": None of these has a legal definition. Treat them as a hint, then check for the specific terms above.

Suppliers that sell to libraries and museums usually list pH, lignin content, buffering and PAT results on every product page. Craft-store scrapbook supplies can be fine too, but read the fine print. "Acid-free" without "lignin-free" is only half the answer.

Not sure about a box or folder you already own? A pH testing pen, about $8–$15, will tell you. Test the storage material, never the keepsake itself, because the pen leaves a mark.

Buy this, avoid this: the materials list

In short: swap anything acidic, sticky, metal or made of PVC for archival-safe storage materials. Here's the full swap list.

The starter kit

Here's what to order for a first box of paper keepsakes. Prices are rough ranges for each category. One box, a pack of folders and a pack of tissue, about $35–$80 together, is enough to begin.

• ☐  1–2 acid-free storage boxes, often sold as document boxes, letter or legal size (about $10–$25 each). Legal size gives certificates and big cards some room.
• ☐  A flat lidded archival box for artwork and anything too large to stand in a folder, if you need one (about $20–$45).
• ☐  A pack of acid-free, lignin-free, buffered file folders (about $15–$35 for 25 or so).
• ☐  A pack of white acid-free tissue, unbuffered (about $10–$20).
• ☐  A pack of archival polyester or polypropylene sleeves for photos and fragile pieces (about $10–$25).
• ☐  A few small acid-free envelopes for ticket stubs, ID cards and ultrasound prints (about $8–$15).
• ☐  A soft pencil, such as a 2B, for labeling (under $2).
• ☐  A digital hygrometer, which is a small temperature and humidity gauge, for the closet (about $10–$20).

What you can skip

• White cotton gloves. For paper, clean, dry hands work better. Gloves make you clumsy and can snag edges. For photos, hold them by the edges or wear nitrile gloves.
• Vacuum-sealed bags. They press creases into paper and trap whatever moisture was inside.
• Silica gel packets. A normal indoor closet doesn't need them. If you use them anyway, keep them well out of children's reach.
• Mothballs and cedar blocks. Paper doesn't need them, and mothballs are toxic to kids and pets.

How to store paper keepsakes, step by step

In short: sort, remove the hazards, flatten, folder, label, box and scan. Plan on an afternoon for the first box.

1. Set up clean. Clear a table, wash and dry your hands, and skip hand lotion. Keep food and drinks on another surface.
2. Sort and edit. Make piles by child, then by type: cards and letters, records, artwork, clippings, and photos and ultrasound prints. Be choosy. A box you can lift and flip through beats three you never open. Our guide to storing baby keepsakes long term has a box-by-age system if you need help deciding what stays.
3. Remove the hazards. Take off rubber bands, paper clips, sticky notes and plastic wrap. For staples, gently lift the prongs from the back with a butter knife, then slide the staple out from the front. If metal has rusted into a precious item, or old tape won't come away easily, leave it. Slip acid-free paper between it and its neighbors and ask a paper conservator.
4. Unfold what opens easily. Paper that stays folded for years can crack along the creases. If a sheet feels stiff, crackles or starts to split, stop and store it folded in its own folder. Never iron paper flat.
5. Separate the troublemakers. Newspaper, thermal prints like ultrasounds, and construction paper each get their own folder, away from everything else. More on these below.
6. Folder by event or type. Use one subject per folder, such as baby shower cards or first-year daycare art. Keep each letter with its envelope. A folder should still close flat; if it bulges, split it in two.
7. Label the folder, not the keepsake. Write in soft pencil on the tab: the child's name, what's inside and the year. For example: "Maya / baby shower cards / 2025" or "Leo / hospital and first week / 2026." If you must label an item, write lightly in pencil on the back, near an edge.
8. Box it right. Stand folders upright and fill the box snugly so nothing slumps, without cramming. If the box is half full, add a folded piece of acid-free board or rolled tissue as a spacer. Oversized, heavy or brittle pieces lie flat in a flat box. Label the outside in pencil, and don't stack anything heavy on top.
9. Scan the ones you can't replace. The box protects the paper. A scan protects against fire, flood and loss. A phone scanning app works for cards and letters; a flatbed scanner is better for photos and artwork. Save copies in two places, and keep the originals.

Which keepsakes need special handling?

In short: a few common baby-year items break the general rules. Handle these on their own.

Ultrasound prints

Most ultrasound prints are on thermal paper, the same kind used for many store receipts. Heat, light and PVC plastic can fade the image, sometimes to nearly blank. Scan them now, while they're sharp, and display a printed copy instead of the original. Store originals flat in their own acid-free envelope or polyester sleeve, and never laminate them, since heat can darken thermal paper.

Hospital bracelets and plastic ID cards

These are plastic, often vinyl, and some vinyl gives off chemicals that harm paper and photos. Keep them out of direct contact with paper, in a small archival polyethylene bag or their own envelope. Non-paper keepsakes like a first-haircut lock of hair need their own small container too.

Newspaper birth announcements and clippings

Newsprint is some of the most acidic paper you'll ever store. It yellows fast and stains whatever it touches. Keep the original alone in a buffered folder. For display or a scrapbook page, use a photocopy or a print of your scan on acid-free paper.

Kids' artwork

Construction paper is acidic and its colors fade quickly, so it gets its own folder. Store all artwork flat, because rolling cracks paint and leaves a permanent curl. Chalk, pastel and charcoal smudge, so lay unbuffered tissue on top and don't let pieces slide against each other. Skip plastic sleeves for these and for anything with glitter or flaky paint, because static can pull loose bits off the page.

Cards and letters

Keep each card with its envelope; the postmark and handwriting are part of the keepsake. Musical cards hold a small button battery. If it comes out easily, remove it before boxing, since old batteries can leak, and get it out of the house right away because button batteries are dangerous if swallowed. If it won't come out, give that card its own envelope and keep the box where little hands can't reach it.

Birth certificates and other vital records

Originals belong with your important papers in a fire-resistant safe or safe deposit box, not in the keepsake box. Put each one in a polyester sleeve or acid-free folder first. Fire-resistant safes can hold damp air, so open yours now and then and check for a musty smell. Don't laminate vital records; lamination is permanent, and many agencies advise against it.

Handwritten recipe cards

Recipe cards get handled with wet, greasy hands. Make copies for the kitchen and box the originals in their own folder, and don't try to clean grease stains yourself. Our guide to a family recipe keepsake book covers collecting and copying them.

Christening gowns, first outfits and blankets follow different rules than paper. For those, see our guide to preserving baby clothes so they last.

Where should you keep the box?

In short: an interior closet on a floor you live on. If you're comfortable in the room year-round, your paper probably is too.

Most preservation guides suggest a spot that stays roughly 60–75°F with relative humidity around 30–50%. Just as important, it shouldn't swing much from season to season. Mold becomes a real risk when humidity stays above roughly 65–70%, and a hygrometer on the shelf shows you what your closet actually does in July and January.

• Good: a hall or bedroom closet shelf, never directly on the floor, away from outside walls.
• Keep away from: windows, heating and cooling vents, radiators, water heaters, bathrooms and walls with plumbing.
• Okay in a pinch: under a bed in a dry bedroom, in a closed box. It gathers more dust and is easier to forget, but it beats the options below. Not for a box holding a musical card with a battery you couldn't remove, or silica gel packets. Those boxes belong on a high closet shelf.
• Avoid: attics, basements, garages and storage units without climate control.

Can you use a plastic bin?

Yes, as an outer shell. Bins made of polypropylene (recycling code 5) or polyethylene (codes 2 and 4) are chemically stable and good against leaks and pests. Put the archival box, or at least the foldered paper, inside, and keep the bin in a dry room so it doesn't seal in damp air. Skip anything marked code 3, which is PVC, and any bin with a strong plastic smell.

If you want to go deeper, the Library of Congress and the National Archives both publish free guidance on caring for family papers.

A 15-minute yearly check

In short: once a year, open the box, look, sniff and add the new year's keepsakes.

Tie it to a date you won't forget, like a child's birthday or the week you pack away outgrown clothes. Then run through this list:

• Sniff for a musty smell and look for fuzzy spots or dark stains.
• Check for pests: tiny holes, droppings or silverfish.
• Look for rust, sticky residue or yellowing that has spread since last year.
• Make sure the box is dry, square and not sagging. Replace any box that got wet or smells stale.
• Read the hygrometer, and note the year's high and low humidity if it records them.
• Add this year's items, foldered and labeled, and scan anything that matters.

If you find mold, don't brush it off indoors. Move the item into its own bag, away from the others, and ask a paper conservator. The American Institute for Conservation runs a free Find a Conservator directory on its website.

Start with one box

You don't have to fix every drawer in the house this weekend. Pick the pile that worries you most, usually the ultrasound prints, the newspaper clipping and the cards from the first weeks. Give it one acid-free box, a pack of folders and a pencil. Once that box is labeled, scanned and sitting on a closet shelf, the rest is just adding to it each year.

Frequently asked questions